CN110622627A - Semiconductor device with a plurality of semiconductor chips - Google Patents

Abstract

A semiconductor device (101) includes a printed circuit board (1), an electronic component (2), and a thermal diffusion part (3). The electronic component (2) and the thermal diffusion part (3) are bonded to one main surface (11a) of the printed circuit board (1). The electronic component (2) and the thermal diffusion part (3) are electrically and thermally bonded by the bonding material (7a). A printed circuit board (1) includes an insulating layer (11) and a plurality of heat dissipation through holes (15) penetrating from one main surface (11a) to the other main surface (11b). At least a part of the plurality of heat dissipation through holes (15) overlaps with the electronic component (2), and at least another part overlaps with the thermal diffusion part (3). At least a part of the plurality of heat-dissipating through holes ( 15 ) is arranged to overlap the heat-dissipating portion ( 4 ) at the transmission viewpoint from the other main surface ( 11 b ) of the printed circuit board ( 1 ).

Description

semiconductor device

technical field

The present invention relates to a semiconductor device, and more particularly, to a semiconductor device having excellent heat dissipation properties against heat generated from electronic components.

Background technique

There are electronic circuits, power supply units, and motors that use semiconductors used in vehicles (automobiles/industrial construction machinery), vehicles (railway vehicles), industrial equipment (processing machines/robots/industrial inverters), and home electronic equipment Such driving circuits are collectively referred to as semiconductor devices hereinafter. In semiconductor devices, there are strong demands for high output, thinning, and miniaturization. Along with this, the calorific value per unit volume of electronic components mounted on semiconductor devices has increased significantly, and a semiconductor device capable of realizing high heat dissipation has been strongly demanded.

For example, Japanese Patent Laid-Open No. 6-77679 (Patent Document 1) and Japanese Patent Laid-Open No. 11-345921 (Patent Document 2) disclose semiconductor devices that dissipate heat generated from electronic components. In these patent documents, the electronic components are bonded to the upper side of the printed circuit board, and the heat sink is bonded to the lower side. A heat conduction path formed so as to penetrate from the one main surface to the other main surface is formed on the printed circuit board. The heat generated from the electronic components is transferred to the heat sink through the heat conduction channel, and the heat can be dissipated from the heat sink to the outside.

prior art literature

Patent Literature

Patent Document 1: Japanese Patent Application Laid-Open No. 6-77679

Patent Document 2: Japanese Patent Application Laid-Open No. 11-345921

SUMMARY OF THE INVENTION

In the apparatus of Japanese Patent Application Laid-Open No. 6-77679, the heat conduction channel is provided only in the printed circuit board at the place far from the electronic component directly below, and in Japanese Patent Application Laid-Open No. 11-345921, only the electronic component in the printed circuit board is provided A hole for heat conduction is provided just below the . Therefore, the area of the heat transferable region in any printed circuit board is small, and the amount of heat that can be conducted from the electronic components is small, so the heat dissipation from the electronic components to the area of the heat sink below it is insufficient. Furthermore, the fastening plate of the apparatus of Japanese Patent Application Laid-Open No. 6-77679 is fixed to the printed circuit board only by a jig, and there is a possibility that an air layer is generated between the printed circuit board and the heat sink and the heat dissipation between the two is insufficient.

The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a semiconductor device capable of radially diffusing heat centered on electronic components, and capable of further improving heat dissipation against heat generated from electronic components.

The semiconductor device of the present invention includes a printed circuit board, electronic components, and a thermal diffusion portion. The electronic component and the thermal diffusion part are bonded to one main surface of the printed circuit board. The electronic parts and the thermal diffusion part are electrically and thermally bonded by the bonding material. The printed circuit board includes an insulating layer and a plurality of heat dissipation through holes penetrating from one main surface to the other main surface. At least a part of the plurality of heat dissipation through holes overlaps with the electronic component, and at least the other part overlaps with the thermal diffusion part. At least a part of the plurality of heat-dissipating through-holes is arranged so as to overlap with the heat-dissipating portion at the transmission viewpoint from the other main surface of the printed circuit board.

ADVANTAGE OF THE INVENTION According to this invention, heat can be radially diffused centering on an electronic component, and it can also dissipate heat directly below an electronic component. Therefore, it is possible to provide a semiconductor device capable of further improving the heat dissipation performance against heat generated from electronic components.

Description of drawings

FIG. 1 is a schematic plan view of a semiconductor device according to a first example of Embodiment 1. FIG.

2 is a schematic cross-sectional view of a semiconductor device according to a first example of Embodiment 1. FIG.

3 is a schematic plan view of a printed circuit board in the first example of Embodiment 1 before mounting of electronic components and thermal diffusion parts.

4 is a schematic plan view of a semiconductor device according to a second example of Embodiment 1. FIG.

5 is a schematic cross-sectional view of a semiconductor device according to a second example of Embodiment 1. FIG.

6 is a schematic cross-sectional view showing a first step of the method of manufacturing the semiconductor device according to the first example of Embodiment 1. FIG.

7 is a schematic cross-sectional view showing a second step of the method of manufacturing the semiconductor device according to the first example of Embodiment 1. FIG.

8 is a schematic cross-sectional view showing a third step of the method of manufacturing the semiconductor device according to the first example of Embodiment 1. FIG.

9 is a schematic plan view showing a heat transfer path from an electronic component in Embodiment 1. FIG.

10 is a schematic cross-sectional view showing a heat transfer path from an electronic component in Embodiment 1. FIG.

11 is a graph comparing thermal resistance values in the semiconductor devices of Embodiment 1 and Comparative Example.

12 is a schematic plan view showing the dimensions of each part of the model of the semiconductor device according to Embodiment 1 used for deriving the graph of FIG. 11 .

13 is a schematic plan view showing a model of the semiconductor device of Embodiment 1 used for deriving the graph of FIG. 11 .

14 is a graph showing the relationship between the distance from the edge of the electronic component to the outermost heat dissipation through hole bonded to the thermal diffusion plate and the thermal resistance of the semiconductor device.

15 is a schematic plan view of a semiconductor device according to each example of Embodiments 2 to 5. FIG.

16 is a schematic cross-sectional view of a semiconductor device according to Embodiment 2. FIG.

17 is a schematic cross-sectional view of a semiconductor device according to Embodiment 3. FIG.

18 is a schematic cross-sectional view showing a first step of the method of manufacturing the semiconductor device according to the third embodiment.

19 is a schematic cross-sectional view showing a second step of the method of manufacturing the semiconductor device according to the third embodiment.

20 is a schematic cross-sectional view showing a third step of the method of manufacturing the semiconductor device according to the third embodiment.

21 is a schematic cross-sectional view showing a fourth step of the method of manufacturing the semiconductor device according to the third embodiment.

22 is a schematic cross-sectional view of a portion of the semiconductor device according to Embodiment 4, taken along the line A-A in FIG. 15 .

23 is a schematic cross-sectional view of a portion of the semiconductor device according to Embodiment 4, taken along the line B-B in FIG. 15 .

24 is a schematic cross-sectional view of a semiconductor device according to a first example of Embodiment 5. FIG.

25 is a schematic cross-sectional view of a semiconductor device according to a second example of Embodiment 5. FIG.

FIG. 26 is a schematic enlarged cross-sectional view showing a more preferable embodiment of the region XXVI surrounded by the dotted line in FIG. 24 .

27 is a schematic plan view of a semiconductor device according to each example of Embodiment 6. FIG.

28 is a schematic cross-sectional view of a semiconductor device according to a first example of Embodiment 6. FIG.

29 is a schematic cross-sectional view of a semiconductor device according to a second example of Embodiment 6. FIG.

30 is a schematic enlarged cross-sectional view showing a part of the semiconductor device according to the seventh embodiment in an enlarged manner.

FIG. 31 is a schematic enlarged cross-sectional view showing a mode of a region XXXI surrounded by a broken line in FIG. 30 .

32 is a schematic enlarged plan view showing a part of the semiconductor device according to the eighth embodiment in an enlarged manner.

33 is a schematic enlarged cross-sectional view showing a part of the semiconductor device according to the eighth embodiment in an enlarged manner.

34 is a schematic plan view of the semiconductor device according to the ninth embodiment.

35 is a schematic cross-sectional view of a semiconductor device according to a first example of the tenth embodiment.

36 is a schematic cross-sectional view of a semiconductor device according to a second example of the tenth embodiment.

37 is a schematic cross-sectional view of a semiconductor device of a comparative example with respect to the first example of the tenth embodiment.

38 is a schematic cross-sectional view of a semiconductor device of a comparative example with respect to the second example of the tenth embodiment.

39 is a schematic cross-sectional view of a semiconductor device according to a first example of Embodiment 11. FIG.

40 is a schematic cross-sectional view of a semiconductor device according to a second example of the eleventh embodiment.

41 is a schematic cross-sectional view of a semiconductor device according to a third example of the eleventh embodiment.

42 is a schematic cross-sectional view of a semiconductor device according to a fourth example of the eleventh embodiment.

43 is a schematic plan view of a semiconductor device according to each example of the twelfth embodiment.

44 is a schematic cross-sectional view of the semiconductor device according to the first example of the twelfth embodiment.

45 is a schematic cross-sectional view of a semiconductor device according to a second example of the twelfth embodiment.

(Symbol Description)

1: printed circuit board; 1A: area; 2: electronic parts; 3: thermal diffusion part; 4: heat dissipation part; 51: frame body; 6a: solder paste; 6b: solder plate; 6c: heat-resistant tape; Bonding material; 8: convex part; 11: insulating layer; 11a: one main surface; 11b: other main surface; 12: upper conductor layer; 13: lower conductor layer; 14: inner conductor layer; 15: Through hole for heat dissipation; 15a: first through hole for heat dissipation; 15b: second through hole for heat dissipation; 15c: conductor film; 15d: slot; 16: filler; 17: glass fiber; 18: epoxy resin; 21: lead wire Terminal; 22: Semiconductor chip; 23: Resin molding part; 23e: Downward facing molding surface; 23f: Upward facing molding surface; 23g: Molding side surface; 24: Heat sink; 24c: Horizontal extension; Vertically extending parts; 31, 31x, 31y, 31z: heat diffusion plate; 31a: first heat diffusion plate part; 31b: second heat diffusion plate part; 31c: third heat diffusion plate part; 31d: fourth heat diffusion plate part; 31f: 5th heat diffusion plate part; 31g: 6th heat diffusion plate part; 41, 52: heat dissipation member; 42: cooling body; 60: heat diffusion material; 71: bulk solder; 101, 102, 201, 301, 401, 501, 502, 601, 602, 701, 801, 901, 1001, 1002, 1101, 1102, 1103, 1104, 1201, 1202: semiconductor devices; H1, H2: heat.

Detailed ways

Hereinafter, one embodiment will be described with reference to the drawings.

Embodiment 1.

FIG. 1 shows the whole or a part of the semiconductor device according to the first example of the present embodiment, in a plan view from above as a see-through viewpoint from above. 2 is a schematic cross-sectional view of a portion taken along the line II-II in FIG. 1 , and shows a laminated structure of the printed circuit board 1 and the heat dissipation portion 4 in a region where the electronic component 2 and the thermal diffusion portion 3 to be described later are arranged. . That is, when FIG. 1 is a part of a semiconductor device, FIG. 1 shows the form which cut|disconnected only a part of the whole semiconductor device. 1 and 2 , the semiconductor device 101 of the first example of the present embodiment is a device used in a power conversion device mounted on a hybrid vehicle, an electric vehicle, an electrical product, an industrial equipment, or the like. The semiconductor device 101 mainly includes a printed circuit board 1 , an electronic component 2 , a thermal diffusion part 3 , and a heat dissipation part 4 . As shown below, the semiconductor device 101 has a path for dissipating heat generated in the electronic component 2 to the outside from the heat dissipation portion 4 below the heat dissipation through hole 15 of the printed circuit board 1 directly under the heat dissipation hole 15 , and a path for dissipating heat to the outside through the heat dissipation through hole 15 of the printed circuit board 1 directly below the semiconductor device 101 . A path for heat dissipation from the heat dissipation part 4 to the outside after the surrounding thermal diffusion parts 3 are released. Hereinafter, it demonstrates in detail. First, the printed circuit board 1 will be described.

The printed circuit board 1 is a flat plate-shaped member having a rectangular shape in plan view, for example, which forms the basis of the entire semiconductor device 100 . As shown in FIG. 2 in particular, the printed circuit board 1 has an insulating layer 11, an upper conductor layer 12 and a lower conductor layer 13 as a plurality of conductor layers, and an inner conductor layer 14 as a plurality of other conductor layers.

The insulating layer 11 is a member that forms the basis of the entire printed circuit board 1 . In the present embodiment, the insulating layer 11 has a rectangular flat plate shape, and is made of, for example, glass fiber and epoxy resin. However, it is not limited to this, For example, it may consist of aramid resin and epoxy resin.

The upper conductor layer 12 is formed on one main surface of the insulating layer 11 , that is, the upper main surface in FIG. 2 . In addition, the lower conductor layer 13 is formed on the other main surface of the insulating layer 11 on the side opposite to the one main surface, that is, the lower main surface in FIG. 2 . However, here, not only the one main surface 11a and the other main surface 11b of the insulating layer 11, but also the upper surface of the upper conductor layer 12 may be the uppermost surface of the entire printed circuit board 1, that is, one of the uppermost surfaces. The main surface 11 a is the other main surface 11 b that is the lowermost surface of the entire printed circuit board 1 , which is the lower surface of the lower conductor layer 13 .

Furthermore, inside the insulating layer 11, the inner conductor layer 14 is formed. The inner conductor layer 14 is arranged to be spaced apart from each of the upper conductor layer 12 and the lower conductor layer 13 with respect to the vertical direction. The inner conductor layer 14 faces each of the upper conductor layer 12 and the lower conductor layer 13 in a substantially parallel manner. That is, the inner conductor layer 14 faces each of the main surfaces of one and the other of the insulating layer 11 so as to be substantially parallel to each other. The inner conductor layer 14 is formed in two layers in FIG. 2 . However, the number of layers in which the internal conductor layers 14 are formed is not limited to this, and the number of layers other than two may be used, or the internal conductor layers 14 may not be formed. However, since the inner conductor layer 14 has higher thermal conductivity than the insulating layer 11 , when the inner conductor layer 14 is arranged, the overall thermal conductivity of the printed circuit board 1 can be improved compared with the case where the inner conductor layer 14 is not arranged.

As described above, the printed circuit board 1 is provided with one layer of the upper conductor layer 12 on one main surface, one layer of the lower conductor layer 13 on the other main surface, and two layers arranged therebetween. The inner conductor layer 14 of the four conductor layers in total is used as a plurality of conductor layers, but is not limited to this. This point is also the same in each subsequent embodiment. These conductor layers 12 , 13 , and 14 all extend (in a substantially parallel manner) along one and the other main surfaces of the printed circuit board 1 . The conductor layers 12 , 13 , and 14 are made of a material having good thermal conductivity, such as copper, and have a thickness of about 15 μm or more and 500 μm or less, respectively. Conversely, the printed circuit board 1 includes a plurality of insulating layers 11 divided by conductor layers 12 , 13 , and 14 .

In the printed circuit board 1 , a plurality of heat dissipation through holes 15 are formed so as to penetrate from one main surface to the other main surface of the insulating layer 11 . From the perspective of transmission from one main surface 11 a of the printed circuit board 1 , the region overlapping the electronic component 2 and the region overlapping the thermal diffusion part 3 are separated from each other in the direction along the one main surface 11 a of the printed circuit board 1 . A plurality of heat dissipation through holes 15 are formed at intervals. Here, the printed circuit board 1 is considered as being divided into a first area and a second area. The first region refers to the region overlapping the electronic component 2 from the transmission viewpoint from one main surface side of the printed circuit board 1 , and the second region refers to the surrounding region, that is, on the one main surface from the printed circuit board 1 . The side transmission viewpoints are arranged in an area outside the first area. At this time, the plurality of heat dissipation through holes 15 are classified into a plurality of first heat dissipation through holes 15a formed in the first region and a plurality of second heat dissipation through holes 15b formed in the second region.

That is, the through-holes 15 for heat dissipation are formed in both the above-mentioned first region and the second region. At least a part of the plurality of heat dissipation through holes 15 is a first heat dissipation through hole 15 a that overlaps with the electronic component 2 from the perspective of transmission from one main surface 11 a of the printed circuit board 1 . In addition, at least the other part of the plurality of heat dissipation through holes 15 is a second heat dissipation through hole 15 b overlapping the thermal diffusion part 3 from the perspective of transmission from one main surface 11 a of the printed circuit board 1 .

The first heat dissipation through hole 15a and the second heat dissipation through hole 15b are holes formed in a part of the insulating layer 11, and a conductor film 15c such as copper is formed on the inner wall surfaces of the holes. Here, the heat dissipation through holes 15 (the first heat dissipation through holes 15a and the second heat dissipation through holes 15b ) may be considered to include both the hole portion and the conductor film 15c inside it, or only the hole portion. or one of the conductor films 15c. That is, in FIG. 2, the 1st through-hole 15a for heat dissipation and the 2nd through-hole 15b for heat dissipation are hole parts (hollow) except the part of the conductor film 15c. However, the first through-holes 15a for heat dissipation and the second through-holes 15b for heat dissipation in FIG. 2 may be examples in which the holes are filled with a material with good thermal conductivity, such as a conductive adhesive mixed with silver filler or solder. . In the latter case, a member such as a conductive adhesive filled in the hole portion can be included in the constituent elements of the heat dissipation through hole 15 . The heat dissipation through hole 15 formed by filling with the conductive adhesive or the like in this way can improve heat dissipation compared to the heat dissipation through hole 15 in which the hole portion is hollow. The reason for this is that the thermal conductivity of conductive members such as conductive adhesives is higher than that of air. In addition, the semiconductor device in which the hole part of the through-hole 15 for heat dissipation is filled with solder is shown in Embodiment 3 mentioned later.

The hole portion of the heat dissipation through hole 15 is, for example, a cylindrical shape having a diameter of 0.6 mm in plan view, and the thickness of the conductor film 15c on the inner wall surface thereof is, for example, 0.05 mm. However, the hole portion is not limited to the cylindrical shape, and may be, for example, a quadrangular prism, and may be a polygonal shape as viewed from above.

The first through-holes 15a for heat dissipation and the second through-holes 15b for heat dissipation intersect with the one main surface 11a and the other main surface 11b of the above-mentioned printed circuit board 1, for example, so as to be perpendicular to each other. In addition, the conductor layers 12 , 13 , and 14 are all arranged so as to extend planarly from the first region to the second region of the printed circuit board 1 so as to follow one and the other main surfaces of the printed circuit board 1 , that is, substantially set in parallel. Therefore, both the first heat dissipation through hole 15 a and the second heat dissipation through hole 15 b are connected to each of the conductor layers 12 , 13 , and 14 to cross each other. Conversely, the plurality of conductor layers 12 , 13 , and 14 are cross-connected to each of the plurality of heat dissipation through holes 15 . More specifically, the conductor film 15c and the conductor layers 12, 13, and 14 formed on the inner wall surface of the hole portion of the heat dissipation through hole 15 are cross-connected to each other. Here, the cross-connection means that conductors are joined and electrically connected to each other.

The conductor layers 12 , 13 , and 14 may be arranged so as to extend in a planar shape to a region overlapping with the printed circuit board 1 (to be more precise, a region other than the region of the printed circuit board 1 that overlaps with the hole portion of the heat dissipation through hole 15 ) Overall. In addition, the conductor layers 12 , 13 , and 14 are preferably arranged at least in the first and second regions, in particular, the region overlapping the region in which the heat dissipation through hole 15 is provided (to be precise, the adjacent pair of heat dissipation through holes 15), and cross-connected with the heat dissipation through holes 15. That is, the plurality of conductor layers 12 , 13 , and 14 may be arranged only in areas where the heat dissipation through holes 15 are provided without extending to the area overlapping the area where the heat dissipation through holes 15 are not formed, such as the area 1A in FIG. 1 . The structure of the area where the area (to be precise, the area sandwiched by the adjacent pair of heat dissipation vias 15 ) overlaps.

FIG. 3 shows a plan view from the perspective of transmission from one main surface 11 a side of the printed circuit board 1 before the electronic component 2 and the thermal diffusion unit 3 to be described later are mounted. Referring to FIG. 3 , the heat dissipation through holes 15 are not formed in the entire area on one main surface 11 a of the printed circuit board 1 . That is, in the region 1A on the left side of FIG. 3 , that is, in the region constituting the connection of the lead terminals 21 of the electronic component 2 described later, the heat dissipation through hole 15 is not formed. However, it is preferable to form the conductor layers 12 , 13 , and 14 so as to extend planarly to both the region 1A and the region where the heat dissipation through hole 15 is formed. Thereby, the effect of diffusing the heat of the electronic component 2 in the conductor layer is enhanced.

The area 1A on one main surface 11a of the printed circuit board 1 is an area where wirings (not shown) are arranged in order to connect the lead terminals 21 of the electronic component 2 . This wiring is used to electrically connect the electronic part 2 and other parts. Moreover, the electrode 19 formed in the same layer as the upper conductor layer 12 is formed in one main surface 11a of the area|region 1A of the printed circuit board 1. As shown in FIG. Then, the lead terminals 21 of the electronic component 2 are bonded to the electrodes 19 provided in a part of the region 1A of the printed circuit board 1 with a bonding material 7 a such as solder. Here, joining means joining a plurality of components together with solder or the like.

1 , 2 , and 3 , the numbers of the heat-dissipating through holes 15 do not match, but the heat-dissipating through holes 15 in these figures correspond to each other. The same applies to the subsequent figures.

1 and 2 , on one main surface 11 a of the printed circuit board 1 , that is, on the upper surface of the upper conductor layer 12 , the electronic component 2 and the thermal diffusion portion 3 are bonded. Next, the electronic component 2 and the thermal diffusion part 3 (including the description about the bonding material 7a partly) will be described.

Electronic components 2 will include from MOSFET (Metal Oxide Semiconductor Field Effect Transistor, Metal Oxide Semiconductor Field Effect Transistor), IGBT (Insulated Gate Bipolar Transistor, Insulated Gate Bipolar Transistor), PNP transistor, NPN transistor, diode, control IC (Integrated Circuit A package in which the semiconductor chip 22 of any one or more elements selected from a group consisting of an integrated circuit) is sealed with a resin mold portion 23 . The electronic part 2 has, for example, a rectangular planar shape. Since such a semiconductor chip 22 is included, the amount of heat generated by the electronic component 2 is very large. Therefore, as shown in FIG. 2 , the electronic component 2 has the heat sink 24 . Then, the heat sink 24 is bonded to one main surface 11a of the printed circuit board 1, that is, to the upper conductor layer 12, using a bonding material 7a such as solder. Thereby, the heat generated from the semiconductor chip 22 of the electronic component 2 can be efficiently dissipated via the heat dissipation plate 24 . When the electronic component 2 has the heat sink 24 like the semiconductor device 101 , the electronic component 2 has the lead terminals 21 , the semiconductor chip 22 , the resin mold 23 , and the heat sink 24 .

One purpose of the heat dissipation plate 24 is to transfer heat from the semiconductor chip 22 to the outside. Therefore, as long as the heat of the semiconductor chip 22 can be transferred to the outside from the lead terminal 21 side, the lead terminal 21 can be arranged as the heat sink 24 and the lead terminal 21 can function as the heat sink 24 . In addition, even if the heat sink 24 of FIG. 2 is electrically insulated from the semiconductor chip 22 by interposing an insulating material therebetween, there is no problem as long as the heat of the semiconductor chip 22 can be transferred to the outside.

In FIG. 2 , the heat dissipation plate 24 is arranged so that a part of the upper surface and the side surface on the left side in FIG. 2 are covered by the resin mold part 23 . Thereby, the heat dissipation plate 24 is fixed to the resin mold portion 23 . However, it is an example, and it is not limited to such a form.

FIG. 4 shows the whole or a part of the semiconductor device according to the second example of the present embodiment, in a plan view from above as a see-through viewpoint from above. 5 is a schematic cross-sectional view of a portion taken along the line V-V in FIG. 4 , and shows a laminated structure of the printed circuit board 1 and the heat dissipation portion 4 in the region where the electronic component 2 and the thermal diffusion portion 3 are arranged. Referring to FIGS. 4 and 5 , the semiconductor device 102 of the second example of the present embodiment has basically the same structure as the semiconductor device 101 , so the same components are denoted by the same reference numerals and the description thereof will not be repeated. However, in the semiconductor device 102 , the electronic component 2 does not have the heat dissipation plate 24 , and the electronic component 2 has the entire lowermost surface of the resin mold portion 23 excluding the portion of the lead terminal 21 , and the lower layer thereof does not sandwich the heat dissipation plate 24 . The so-called fully molded structure in which the bonding material 7a contacts. In this point, the semiconductor device 102 is different from the semiconductor device 101 . That is, the electronic component 2 of the semiconductor device 102 includes the lead terminals 21 , the semiconductor chip 22 , and the resin mold portion 23 . Since the resin mold portion 23 is not easily joined by, for example, solder, which is a bonding material of the lower layer, it has a structure that is in close contact with the bonding material only. As long as the resin mold portion 23 of the electronic component 2 is in a state of being in contact with at least the bonding material, heat dissipation from there to the printed circuit board 1 side can be ensured to some extent. Here, close contact means that a plurality of members are in contact with each other, and an attractive force weaker than that of joining is generated with each other.

Referring again to FIGS. 1 and 2 , the thermal diffusion portion 3 has a role of radially diffusing the heat from the electronic component 2 to the outside from a transmission viewpoint above the electronic component 2 . Therefore, the thermal diffusion portion 3 has a shape surrounding the side surfaces of the three sides other than the left side in FIG. 1 , which is the lead terminal 21 side of the rectangular electronic component 2 . By setting it as such a shape, the thermal-diffusion part 3 can improve the efficiency of diffusing the heat from the electronic component 2 radially. However, the thermal diffusion portion 3 is not necessarily limited to such a shape.

The thermal diffusion part 3 includes a thermal diffusion plate 31 . The thermal diffusion plate 31 is preferably formed of, for example, copper. Thereby, the thermal conductivity of the thermal diffusion plate 31 , that is, the heat dissipation can be improved. The thermal diffusion plate 31 may be formed of a ceramic material having good thermal conductivity, such as aluminum oxide or aluminum nitride, on which a metal film such as copper is formed. In addition, the thermal diffusion plate 31 may be formed of a metal material in which a nickel-plated film and a gold-plated film are formed on the surface of an arbitrary alloy material selected from the group consisting of copper alloy, aluminum alloy, and magnesium alloy. This thermal diffusion plate 31 is bonded to one main surface 11 a of the printed circuit board 1 , that is, to the upper conductor layer 12 by a bonding material 7 a such as solder. In addition, the electronic component 2 is bonded to the upper conductor layer 12 to which the thermal diffusion plate 31 is bonded by the bonding material 7a. The portion of the upper conductor layer 12 to which the thermal diffusion plate 31 is bonded and the portion of the upper conductor layer 12 to which the electronic component 2 is bonded are integrated. Therefore, the electronic component 2 is bonded to the same upper conductor layer 12 as the portion to which the upper conductor layer 12 of the thermal diffusion plate 31 is bonded. However, the electronic component 2 is joined at a position different from the position joined to the thermal diffusion plate 31 from a transmissive viewpoint from above. Furthermore, the thermal diffusion plate 31 and the electronic component 2 are electrically connected.

As shown in FIG. 2 , when solder is used as the bonding material 7 a, the bonding material 7 a between the electronic component 2 and the thermal diffusion part 3 is at the end of the electronic component 2 on the thermal diffusion part 3 side and at the end of the thermal diffusion part 3 . Each of the ends on the electronic component 2 side is rounded. As a result, compared to the thickness of the bonding material 7a between the electronic component 2 and the upper conductor layer 12 and the thickness of the bonding material 7a between the thermal diffusion part 3 and the upper conductor layer 12, the heat sink 24 and the upper conductor layer 12 can be made larger. The thickness of the bonding material 7 a in the region between the thermal diffusion plates 31 .

The heat dissipation plate 24 which is the electronic component 2 and the thermal diffusion plate 31 which is the thermal diffusion part 3 are electrically and thermally connected by a bonding material 7a such as solder. In addition, the electrical connection between the electronic component 2 and the thermal diffusion part 3 means that the two are connected not by an insulating material but by a member called a conductive material such as solder having a low resistance value. In addition, the thermal connection between the electronic component 2 and the thermal diffusion part 3 means that the two are not connected by a heat insulating material but by a material called a low thermal resistance value such as solder, for example.

More specifically, the heat dissipation plate 24 of the electronic component 2 and the thermal diffusion plate 31 of the thermal diffusion part 3 are joined via the bonding material 7a so as to be aligned in the left-right direction of FIG. 2 . If the thermal diffusion plate 31 is made of a conductive material such as a metal material, electricity is supplied to the thermal diffusion plate 31 joined to the electronic component 2 by the bonding material 7a such as solder, so that the upper conductor in the printed circuit board 1 can be reduced. Resistance value of layer 12 etc. Thereby, the thermal diffusion plate 31 can not only diffuse the heat from the electronic component 2 but also can reduce the conduction loss of the upper conductor layer 12 and the like formed on the printed circuit board 1 . In addition, since both the electronic component 2 and the thermal diffusion part 3 are bonded to the same surface, that is, to one main surface 11a of the printed circuit board 1, for example, the same automatic component mounter (mounter) or the like can be used. , automatically joins the two regardless of the order in which they are joined. Therefore, the process of mounting both on the printed circuit board 1 can be simplified, and the process can be performed efficiently at low cost.

However, when the package of the electronic component 2 is, for example, the semiconductor package type TO-252, the size thereof varies by about ±0.2 mm. Not limited to the above-mentioned models, the package of the electronic component 2 generally has a variation in the size of ±0.01 mm or more and 1 mm or less. Therefore, it is preferable that the distance between the electronic component 2 and the thermal diffusion part 3 be 0.05 mm or more and 5 mm or less, including the error in the drive dimension of the automatic component mounting machine. When the distance between the electronic component 2 and the thermal diffusion portion 3 exceeds 5 mm, the thermal resistance between the electronic component 2 and the thermal diffusion portion 3 increases, and the effect of thermal diffusion by the thermal diffusion portion 3 decreases. Therefore, it is preferable that the space|interval of the electronic component 2 and the thermal diffusion part 3 is 5 mm or less. When the error of the drive dimension of an automatic component mounting machine is large, there exists a possibility that the space|interval of the electronic component 2 and the thermal diffusion part 3 may exceed 5 mm. Therefore, from the viewpoint of preventing such an inconvenience, it is preferable to temporarily fix the electronic components 2 and the thermal diffusion section 3 before mounting the electronic components 2 and the thermal diffusion section 3 on the printed circuit board 1, and then simultaneously mount the electronic components with an automatic component mounting machine. 2 and the thermal diffusion part 3. Thereby, the space|interval of the electronic component 2 and the thermal diffusion part 3 can be made into 5 mm or less, and the yield of a mounting process can be improved.

As described above, the thermal diffusion portion 3 is joined to the electronic component 2 by the joining material 7 a such as solder, and is joined to one main surface 11 a of the printed circuit board 1 . Thereby, the heat emitted from the electronic component 2 can be diffused in the direction of one main surface 11a so as to be radially transmitted to the thermal diffusion part 3 via the bonding material 7a. Moreover, the electronic component 2 is joined to one main surface 11a by the joining material 7a. Therefore, both direct heat transfer from the electronic component 2 to the heat dissipation portion 4 directly below and heat transfer from the thermal diffusion portion 3 to the heat dissipation portion 4 directly below after diffusion from the electronic component 2 to the heat dissipation portion 3 can be realized.

In addition, the thermal diffusion plate 31 is formed by extending the hole portion of the plurality of second heat dissipation through holes 15b in the second region other than the region overlapping with the electronic component 2 among the plurality of heat dissipation through holes 15 of the printed circuit board 1 from the heat dissipation plate 31 . It is bonded to one main surface 11a of the printed circuit board 1 with the bonding material 7a in the form of the upper part being closed. On the other hand, the heat dissipation plate 24 of the electronic component 2 is formed by connecting the plurality of first heat dissipation through holes 15 a in the above-mentioned first region of the plurality of heat dissipation through holes 15 of the printed circuit board 1 in the region overlapping the electronic component 2 . The hole is joined to one main surface 11a of the printed circuit board 1 by the joining material 7a so that the hole is closed from above. In FIGS. 1 and 2 , since the heat dissipation through hole 15 is not formed in the region 1A, the thermal diffusion plate 31 is not arranged, but the present invention is not limited to this.

When solder is used as the bonding material 7a for bonding the above components, an intermetallic is formed at the bonding interface between the bonding material 7a and the electronic component 2, the upper conductor layer 12, and the thermal diffusion plate 31 bonded thereto. The compound can reduce the thermal contact resistance in the bonding interface. Therefore, it is preferable to use solder as the bonding material 7a, but a material having good thermal conductivity other than solder such as a conductive adhesive or nano-silver can also be used.

It is preferable that the thermal diffusion part 3 has higher bending rigidity than the printed circuit board 1 , that is, the product of the Young's modulus and the second moment of section is larger. Thereby, the rigidity of the structure including the printed circuit board 1 and the thermal diffusion plate 31 in the semiconductor device 101 can be improved, and the printed circuit board 1 can be less easily deformed against external forces such as fixing and vibration.

When the thickness of the thermal diffusion plate 31 is reduced, the thermal conductivity decreases, and the heat dissipation with respect to the electronic component 2 becomes insufficient. On the other hand, if the thermal diffusion plate 31 is too thick, the thermal diffusion plate 31 cannot be mounted using the same chip mounter as the chip mounter on which the electronic component 2 is mounted. The reason for this is that the thickness of the thermal diffusion plate 31 exceeds the upper limit value of the thickness of the parts that can be mounted by the chip mounter. As a result, since the installation of the thermal diffusion plate 31 using automatic equipment cannot be realized, the installation cost increases. Considering the above, the thickness of the thermal diffusion plate 31 is preferably 0.1 mm or more and 100 mm or less, and preferably 0.5 mm, for example.

The thick thermal diffusion plate 31 may be formed not in a plate shape but in a block shape. In addition, the thermal diffusion part 3 may have a structure in which a plurality of thermal diffusion plates 31 are stacked. By forming the thermal diffusing portion 3 by stacking commonly used plates, the manufacturing cost thereof can be reduced, and the heat dissipation performance of the thermal diffusing portion 3 can be improved.

Next, the heat dissipation unit 4 will be described. The heat dissipation part 4 is laminated|stacked on the other main surface 11b side of the printed circuit board 1, for example, the whole surface, and has the heat dissipation member 41 and the cooling body 42. The printed circuit board 1 and the heat dissipation portion 4 may be bonded to each other by, for example, the bonding material 7a, or may be in close contact with each other, for example, only in contact. In the semiconductor device 101 of FIG. 2 , as an example, the electronic component 2 , the printed circuit board 1 , the heat dissipation member 41 , and the cooling body 42 are stacked in this order from the upper side toward the lower side in FIG. 2 . However, in the heat dissipating portion 4, the cooling body 42 and the heat dissipating member 41 may be stacked in this order from the upper side toward the lower side in FIG. 2, for example, in the reverse order of the above. That is, the stacking order of the heat-dissipating member 41 and the cooling body 42 in the heat-dissipating portion 4 is not limited.

When the heat dissipation portion 4 is stacked on the entire surface on the other main surface 11 b side of the printed circuit board 1 , the heat dissipation portion 4 is arranged so as to be connected to all the first heat dissipation through holes 15 a and the second heat dissipation through holes of the printed circuit board 1 . 15b overlaps when viewed from above. However, in the present embodiment, at least a part of the plurality of heat dissipation through holes 15 is arranged so as to overlap the heat dissipation portion 4 at the transmission viewpoint from the other main surface 11 b of the printed circuit board 1 . In this sense, the heat dissipation portion 4 may be formed to overlap only at least a part of the other main surface 11 b of the printed circuit board 1 . For example, the heat dissipation member 41 and the cooling body 42 may be arranged so as to be in close contact with the other main surface 11b of the region overlapping with the electronic component 2 in plan view and the region adjacent thereto.

The heat dissipating member 41 is preferably made of a material having electrical insulating properties and good thermal conductivity. Specifically, the heat dissipating member 41 is preferably formed of a sheet in which particles such as alumina or aluminum nitride are mixed into silicone resin. The reason for this is that aluminum oxide or aluminum nitride has good thermal conductivity and electrical insulating properties. However, the heat dissipation member 41 may be grease or adhesive instead of the above. In addition, the heat dissipation member 41 may be a non-silicon type as long as the thermal conductivity is high.

The heat dissipation member 41 may also include a conductor layer and an electrical insulating layer with good thermal conductivity. The heat dissipation member 41 diffuses the heat from the electronic component 2 to the outside of the electronic component 2 through the thermal diffusion plate 31 , and transfers the diffused heat to the lower conductor layer 13 of the printed circuit board 1 through the heat dissipation through hole 15 . If the heat dissipating member 41 has a thermally diffusible conductor layer, the conductor layer can further radially diffuse heat to the outside in a plan view.

The cooling body 42 is a rectangular flat plate-shaped member made of a metal material with good thermal conductivity. The cooling body 42 may be, for example, a frame, a heat pipe, a heat sink, or the like. Specifically, the cooling body 42 is preferably made of, for example, aluminum, but may be made of copper, an aluminum alloy, or a magnesium alloy. The cooling body 42 is arranged directly below or directly above the heat dissipation member 41 . Therefore, in FIG. 2 , the cooling body 42 is thermally connected to the printed circuit board 1 via the heat dissipation member 41 . In other words, the heat dissipating member 41 is in close contact with or joined to the main surface of the upper or lower side of the cooling body 42 . In addition, although not shown in the figure, it is preferable that a cooling mechanism of water cooling or air cooling is provided in contact with the lower side of the cooling body 42 .

FIGS. 6 to 8 are schematic cross-sectional views showing modes in each manufacturing process of the semiconductor device 101 according to the first example of the present embodiment. Next, the outline of the manufacturing method of the semiconductor device 101 will be described with reference to FIGS. 6 to 8 , especially focusing on the mounting process of the electronic component 2 and the thermal diffusion portion 3 .

6 , a printed circuit board 1 having the aspect shown in FIG. 2 is prepared, and a solder paste 6 a is supplied on one main surface 11 a , that is, on the upper conductor layer 12 . For example, it is preferable to supply a plurality of solder pastes 6 a in a plan view to each of the regions sandwiched between a pair of mutually adjacent heat dissipation through holes 15 formed on the printed circuit board 1 . The solder paste 6a is preferably printed by, for example, a generally known printing method in a region separated by 100 μm or more from the outer edge of each of the plurality of heat dissipation through holes 15 in the direction along one main surface 11a of the printed circuit board 1 .

By using a metal mask, a generally known solder printing process is performed, and as shown in FIG. 6 , a solder paste 6 a is supplied onto the printed circuit board 1 .

7 , the electronic component 2 and the thermal diffusion plate 31 , which is the thermal diffusion portion 3 , are mounted on the solder paste 6 a , and a generally known heat reflow process is performed in this state. In addition, the process of mounting the electronic component 2 and the thermal diffusion part 3 is performed as an automatic process by the above-mentioned chip mounter. By the reflow process, the solder paste 6a is melted and flows along one main surface 11a, which is the surface of the upper conductor layer 12, to form a layered bonding material 7a. In addition, the bonding material 7a which melts and flows at this time does not flow into the first through hole 15a for heat dissipation and the second through hole 15b for heat dissipation. The reason for this is that, in the process of FIG. 6 , the solder paste 6 a is printed on the regions separated from the first heat dissipation through holes 15 a and the second heat dissipation through holes 15 b. The bonding material 7a also flows directly below the resin mold portion 23 of the electronic component 2, but the bonding material 7a only contacts the resin mold portion 23 and adheres closely to the resin material without bonding. The bonding material 7a bonds the heat dissipation plate 24, the thermal diffusion plate 31, and the upper conductor layer 12 of the electronic component 2 to each other. In addition, this bonding material 7a joins the lead terminals 21 of the electronic component 2 and the electrodes 19 of the printed circuit board 1 to each other. After joining by the joining material 7a, an appearance inspection process for inspecting the attached state is performed.

8 , for example, a heat dissipation member 41 and a cooling body 42 are arranged in order from the upper side to the lower side so as to be in contact with the lower conductor layer 13 of the printed circuit board 1 and are in close contact with each other, thereby providing the heat dissipation portion 4 . In addition, contrary to the above, the cooling body 42 may be arranged on the upper side and the heat radiating member 41 may be arranged on the lower side by stacking, thereby providing the heat radiating portion 4 . Alternatively, each of these members may be joined by the joining material 7a or the like. Through the above, the semiconductor device 101 shown in FIG. 2 is formed.

Next, the effects of the present embodiment will be described with reference to FIGS. 9 to 14 . In addition, the content and description of the effects of the above-mentioned components may partially overlap.

FIG. 9 shows a heat conduction path from a transmissive viewpoint from above the entire semiconductor device 101 . FIG. 10 shows a heat conduction path in a cross-sectional view of the semiconductor device 101 along the X-X-ray portion of FIG. 9 . Referring to FIGS. 9 and 10 , a part of the heat generated from the electronic component 2 by the driving of the semiconductor device 101 is shown as heat H1 indicated by an arrow in FIG. 1. The through hole 15a for heat dissipation is transmitted to the lower side (the side of the heat dissipation part 4). At the same time, although not shown, the heat H1 passes through the upper conductor layer 12 , the lower conductor layer 13 or the inner conductor layer 14 , so that the heat is directed toward the periphery (outside) of the electronic component 2 in FIG. 10 . The second area of is spread radially.

In addition, the other part of the heat generated from the electronic component 2 is conducted to the thermal diffusion that is joined to the electronic component 2 via the bonding material 7a in the direction along the main surface indicated by the heat H2 indicated by the arrow in FIG. 9 and FIG. 10 . The plate 31 is radially diffused to the outside in the direction along the main surface within the thermal diffusion plate 31 . The reason for this is that the bonding material 7a for bonding the electronic component 2 and the thermal diffusion plate 31 is a conductive material such as solder, and is excellent in thermal conductivity. In addition, the heat transferred to the thermal diffusion plate 31 is conducted to the lower side (the side of the heat dissipation portion 4 ) via the second heat dissipation through holes 15 b of the printed circuit board 1 formed therebelow. A part of the heat H2 passing through the second heat dissipation through hole 15b passes through the upper conductor layer 12, the lower conductor layer 13, or the inner conductor layer 14, so that the heat is directed toward the periphery of the electronic component 2 in FIG. 10 . The second region (outside) spreads radially.

In this way, in the present embodiment, the heat of the electronic component 2 can be transmitted to the lower side (the heat dissipation part 4 side) through the first heat dissipation through hole 15a (the path of the heat H1 indicated by the arrow) and the second heat dissipation through hole 15a. The through-hole 15b conducts the two routes of the route (the route of the heat H2 indicated by the arrow) to the outside (second region side). The reason why the heat can be conducted through two routes in this way is that the thermal diffusion plate 31 is joined to one of the main surfaces 11 a similarly to the electronic components 2 , so that the heat H2 generated from the electronic components 2 is efficiently transmitted to the thermal diffusion plate via the bonding material 7 a 31, the heat H2 can be efficiently conducted to the heat dissipation part 4 from there. The reason for this is that the heat dissipation through holes 15 a and 15 b extending in the direction intersecting the main surface of the printed circuit board 1 and the conductor layers 12 , 13 and 14 extending along the main surface are cross-connected to each other. This effect is further enhanced by the existence of the thermal diffusion plate 31 and the heat dissipation portion 4 arranged on the other main surface 11 b of the printed circuit board 1 .

The heat H1 and the heat H2 moving downward in the printed circuit board 1 reach the lower conductor layer 13 in both the regions immediately below and outside the electronic component 2 and the thermal diffusion plate 31 . Next, the heat H1 and the heat H2 are conducted to the cooling body 42 via the heat dissipation member 41 on the lower side thereof. Although not shown, the heat H1 and the heat H2 conducted to the cooling body 42 are dissipated to, for example, a water cooling or air cooling cooling mechanism provided on the lower side in FIG. 10 .

As described above, the semiconductor device 101 of the present embodiment has the thermal diffusion plate 31 bonded to one of the main surfaces 11 a similarly to the electronic components 2 , so that the heat of the electronic components 2 can be radiated from the thermal diffusion plate 31 through the first heat dissipation through holes 15 a. A structure in which heat is dissipated downward in both directions, a route and a route through the second heat dissipation through hole 15b. Therefore, compared with the case where heat can be dissipated only from the first heat dissipation through hole 15a directly below the electronic component 2, for example, or the heat dissipation can be greatly improved, for example, only from the second heat dissipation through hole 15b separated from the electronic component 2 Efficiency of heat dissipation to the bottom.

In particular, since the thermal diffusion plate 31 is arranged, the effect of improving the heat dissipation efficiency from the second heat dissipation through holes 15b in the semiconductor device 101 of the present embodiment is very large. By disposing the thermal diffusion plate 31 , it is possible to efficiently dissipate heat to the cooling body 42 via the heat dissipating member 41 as compared with the case where the thermal diffusion plate 31 is not disposed.

Further, in the semiconductor device 101 of the present embodiment, for example, as shown in FIG. 1 and FIG. Thereby, not only can the heat generated from the electronic component 2 be transferred downward through the heat dissipation through holes 15 in the regions immediately below the electronic component 2 and the thermal diffusion plate 31 , but also the heat generated from the thermal diffusion plate 31 can be directed to the outside thereof. The diffused heat is transferred downward through the heat dissipation through hole 15 directly below.

Furthermore, as described above, the conductor layers 12 , 13 , and 14 can radially diffuse the heat H1 and H2 of the electronic component 2 toward the outer peripheral side, similarly to the thermal diffusion plate 31 .

As described above, heat is dissipated to the outside, so that the area of the region capable of dissipating heat increases, and the effect of improving heat dissipation becomes greater. Therefore, if the contact area between the cooling body 42 for heat dissipation and the printed circuit board 1 is sufficiently increased, the heat dissipation can be further improved.

Here, with reference to FIG. 11 , it will be described to what extent the heat dissipation efficiency is improved compared with the case where only the heat dissipation through holes 15 and the thermal diffusion plate 31 are provided. Specifically, a structure having both the heat dissipation through hole 15 and the thermal diffusion plate 31 like the semiconductor device 101 and a comparative example without the second heat dissipation through hole 15 b and the heat diffusion plate 31 are shown using thermal resistance values. The result obtained by the radiation resistance (radiation resistance) by the heat conduction of the structure (having only the 1st heat dissipation through-hole 15a).

Here, "thermal resistance" refers to an index showing the difficulty of temperature transfer, and means a temperature rise value per unit of calorific value. In the semiconductor device 101 of the present embodiment, the thermal resistance (R _th ) of the region in the vertical direction from the electronic component 2 to the housing is represented by the following formula (1). In addition, in the formula (1), the heat transfer area of each member is S _i (m ² ), the thickness of each member is l _i (m), and the thermal conductivity of each member is λ _i (W /(m·K)), let the passing heat be Q (W), and the temperatures of the high temperature side and the low temperature side are respectively Th _i (K) and _Tli (K).

[Formula 1]

Here, the model used in the calculation of the thermal resistance is shown. The size from the transmission viewpoint from above the printed circuit board 1 is 25×25 mm, and the thickness is 1.65 mm. The size from the transmission viewpoint from above the electronic component 2 is 10×10 mm, and it is bonded (though different from FIG. 1 and FIG. 4 , etc.) to the central portion of the printed circuit board 1 . That is, the distance between each edge part when the electronic component 2 is seen from above and each edge part when the printed circuit board 1 which opposes substantially parallel to it is seen from above is substantially equal. The upper conductor layer 12 , the lower conductor layer 13 , and the inner conductor layer 14 have a four-layer structure with a thickness of 105 μm (see FIG. 2 ). In the printed circuit board 1, 25 places of the first heat dissipation through holes 15a are arranged at equal intervals directly below the electronic components 2, and 63 places of the second heat dissipation through holes 15a are arranged at equal intervals around the printed circuit board 1. hole 15b. The heat dissipation through hole 15 has a cylindrical shape, the diameter of the hole portion is 0.6 mm when viewed from above, and the thickness of the conductor film on the inner wall surface of the hole portion is 0.05 mm.

In addition, the thermal diffusion plate 31 of the thermal diffusion unit 3 in the above-mentioned model has an outer dimension of 5×15 mm and a thickness of 1 mm from the upper perspective, and is arranged to surround the electronic component 2 and to cover the second heat dissipating heat sink from above. hole 15b. In addition, the electronic component 2 and the thermal diffusion plate 31 arranged in the direction along the main surface are joined to each other by the bonding material 7a of solder. The size of the heat-dissipating member 41 in the transmissive viewpoint from above is 5×15 mm, and the thickness is 0.4 mm.

The upper conductor layer 12 , the lower conductor layer 13 , the inner conductor layer 14 , the conductor film 15 c , and the thermal diffusion plate 31 in the above model are made of copper, and the thermal conductivity is 398 W/(m·K). In addition, the thermal conductivity of the heat dissipation member 41 was 2.0 W/(m·K).

The model of the semiconductor device 101 of this embodiment and the model of the comparative example have only the number of the heat dissipation through holes 15 (the comparative example has only the first heat dissipation through holes 15 a, but the present embodiment has the first heat dissipation through holes 15 a ). The through-hole 15a and the second heat-dissipating through-hole 15b) and the presence or absence of the thermal diffusion plate 31 are different, and other structures including the above-mentioned dimensions are all the same.

Using the above-described model, the thermal resistance value was simulated using the thermal analysis software based on the formula (1) for the semiconductor device 101 and the comparative example. Figure 11 shows the results. "ref" in FIG. 11 means the model of the comparative example, "through hole+thermal diffusion plate" means the model of the semiconductor device 101 of the present embodiment, and the vertical axis shows the simulation result of thermal resistance. 11 , by providing the second heat dissipation through holes 15b and the thermal diffusion plate 31 as in the semiconductor device 101 of the present embodiment, the thermal resistance can be reduced by about 53% compared to the comparative example in which these are not provided. Small thermal resistance means high heat dissipation, so it can be seen from the results that by providing the second heat dissipation through holes 15b and the thermal diffusion plate 31 as in the semiconductor device 101 of the present embodiment, compared with the comparative example in which these are not provided, it is possible to Improve heat dissipation.

Next, the results obtained by examining the regions where the heat dissipation through holes 15 bonded to the thermal diffusion plate 31 should be arranged will be described with reference to FIGS. 12 to 14 . Referring to FIGS. 12 and 13 , which show basically the same model as the semiconductor device 101 of the present embodiment used in the calculation of the thermal resistance described above, L1 , L2 , and L3 denote various directions when the electronic component 2 is viewed from above. The distance between the edge portion and the outermost edge portion in each direction of the thermal diffusion plate 31 adjacent to the outside when viewed from above. As described above, in this model, the distances between the edge in each direction and the edge in each direction of the thermal diffusion plate 31 adjacent thereto when the electronic component 2 is viewed from above are substantially equal, so the distances L1 to L3 are substantially equal. In addition, in the semiconductor device 101, basically, the second heat dissipation through hole 15b is not formed in the region 1A (see FIG. 1 ), and the second heat dissipation through hole 15b does not exist on the side of L4 in FIGS. 12 and 13 . Dimension L4 is also shown in this direction as in the other directions for reference.

The horizontal axis of the graph of FIG. 14 represents the highest point of the thermal diffusion plate 31 from each edge (corresponding to the rectangular side) to the side in the three directions of L1 to L3 where the thermal diffusion plate 31 is arranged in a plan view of the electronic component 2 . For the distance from the outside, the vertical axis of the graph represents the thermal resistance value of the semiconductor device 101 of each model. 14 , as the sizes of L1 to L3 become larger (that is, as the regions formed by the thermal diffusion plate 31 and the second heat dissipation through holes 15b become wider), the thermal resistance becomes smaller and the heat dissipation efficiency improves. However, it can be seen that when the values of L1 to L3 are 20 mm, the decrease in the thermal resistance value is saturated, and even if L1 to L3 are further increased, the thermal diffusion plate 31 and the heat dissipation plate 31 in the region of L1 to L3 of 20 mm or more are joined by the bonding material 7a. In the through hole 15, the amount of change in thermal resistance value is smaller than that in the region where L1 to L3 are 20 mm or less.

Therefore, it can be said that the thermal diffusion plate 31 is preferably disposed within the range of the dimensions L1 to L3, that is, the distance from the edge of the electronic component 2 within 20 mm, and is joined to the second heat dissipation through hole 15b.

Furthermore, in the present embodiment, not only the first heat dissipation through holes 15a in the first region of the printed circuit board 1 but also the second heat dissipation through holes 15b are formed in the second region around the printed circuit board 1 . Therefore, the mechanical rigidity of the printed circuit board 1 is lowered compared to the case where the second heat dissipation through hole 15b is not formed. However, by bonding the thermal diffusion plate 31 to the upper conductor layer 12 on one main surface 11a of the printed circuit board 1 with the bonding material 7a, the flexural rigidity of the structure including the printed circuit board 1 and the thermal diffusion plate 31 is higher than that of the printed circuit board 1 Bending stiffness of the monomer. Therefore, deformation of the printed circuit board 1 can be suppressed.

Embodiment 2.

FIG. 15 summarizes the whole or a part of the semiconductor devices of the respective examples of Embodiments 2 to 5, which are viewed from above, that is, in a plan view from above. 16 is a schematic cross-sectional view of a portion taken along the line A-A in FIG. 15 in Embodiment 2, showing a laminated structure of the printed circuit board 1 and the heat dissipation part 4 in the region where the electronic component 2 and the thermal diffusion part 3 are arranged. Referring to FIGS. 15 and 16 , the semiconductor device 201 of the present embodiment has basically the same structure as the semiconductor device 101 , so the same components are denoted by the same reference numerals and the description thereof will not be repeated. However, in the semiconductor device 201, the region on the upper conductor layer 12 adjacent to the first heat dissipation through hole 15a and the second heat dissipation through hole 15b in plan view surrounds the first heat dissipation through hole 15a and the second heat dissipation through hole 15b. For example, a circular convex portion 8 is formed around the second heat dissipation through hole 15b. In this point, the semiconductor device 201 is different from the semiconductor device 101 which does not have such a convex portion 8 .

The convex portion 8 is formed of, for example, a solder resist, and has a shape extending upward in FIG. 16 rather than the upper conductor layer 12 . In this way, in the present embodiment, the convex portion 8 is arranged on one main surface 11 a of the printed circuit board 1 . And the electronic component 2 and the thermal diffusion part 3 are arrange|positioned so that it may overlap with the convex part 8 in the transmission viewpoint from one main surface 11a of the printed circuit board 1. As shown in FIG. Moreover, the convex part 8 is formed in the periphery of the plane view of the through-hole 15 for heat dissipation so that it may have a circular shape or an elliptical shape in the cross-sectional view of FIG. 16 . However, the present invention is not limited to this, and the convex portion 8 may be formed, for example, to have a rectangular shape in the cross-sectional view of FIG. 16 .

The manufacturing method of the semiconductor device 201 of this embodiment, especially the manufacturing method of the convex part 8 is demonstrated briefly. The convex portion 8 may be, for example, a solder resist formed by generally known resist printing in a manufacturing process of a printed circuit board, or may be a pattern formed by generally known silk printing or symbol printing. If these are used, since the convex part 8 can be formed by a general printed circuit board manufacturing process, it can manufacture inexpensively without a special process. Moreover, as the convex part 8, other than a solder resist, a wire, and a symbol mark, the example in which a resin sheet was formed may be sufficient, and these may be combined suitably. Furthermore, the convex portion 8 can be a shape having a thickness other than the above-mentioned extending from the upper conductor layer 12 upward in FIG. 16 , and a material that is difficult to wet by the solder bonding material 7a may be used. On the convex part 8 formed in one main surface 11a of the printed circuit board 1, the electronic component 2 and the thermal diffusion plate 31 are mounted and joined so that it may overlap.

Next, the effects of the present embodiment will be described. In addition to the same effects as those of Embodiment 1, the present embodiment has the following functions and effects.

When the bumps 8 are formed like the semiconductor device 201 , the bumps 8 have the effect of suppressing the inconvenience of the solder paste 6a (see FIG. 6 ) entering the holes such as the first heat dissipation through holes 15a. By forming the convex portion 8 , the distance between the upper conductor layer 12 , the heat dissipation plate 24 and the thermal diffusion plate 31 with respect to the vertical direction in FIG. 16 becomes wider than that in the case where the convex portion 8 is not formed. Therefore, in the spaced region, the bonding material 7a formed by melting the solder paste 6a is joined to the heat dissipation plate 24 and the heat dissipation plate 31 while receiving stress so as to be stretched to the upper side, that is, to the heat dissipation plate 24 and the heat dissipation plate 31 side. Diffuser plate 31 . Therefore, in the region between the upper conductor layer 12 , the heat dissipation plate 24 and the thermal diffusion plate 31 , the bonding material 7 a can flow into the heat dissipation through hole 15 and flow on the inner wall surface of the heat dissipation through hole 15 . sex. As a result, it is possible to reduce the possibility that the bonding material 7a short-circuits the upper conductor layer 12 and the cooling body 42 directly under the bonding material 7a, thereby improving the reliability of the semiconductor device 201 as a whole.

Next, by placing the electronic components 2 and the thermal diffusion plate 31 so as to overlap with the protrusions 8 on the upper conductive layer 12 , the area between the upper conductive layer 12 and the heat dissipation plate 24 and the thermal diffusion plate 31 can be controlled. , the interval relative to the vertical direction in FIG. 16 . That is, the distance between the electronic component 2 and the thermal diffusion plate 31 bonded to the printed circuit board 1 and the upper conductor layer 12 can be controlled by changing the printing position or printing thickness of the solder resist or wire as the convex portion 8 . In this way, the thickness of the bonding material 7a on the upper conductor layer 12 can be managed by the convex portion 8, and the quality of the welding using the bonding material 7a can be improved. Although the bonding material 7a spreads along the main surface in the region between the upper conductor layer 12 and the heat dissipation plate 24 and the thermal diffusion plate 31, it does not flow into the heat dissipation through hole 15, and as a result, the bonding material 7a does not reach the lower conductor Layer 13 side. Therefore, with the bonding material 7a, the junction part of the heat sink 24 of the electronic component 2 and the thermal diffusion plate 31 of the thermal diffusion part 3 and the printed circuit board 1 can be well rounded. As a result, it is possible to easily determine whether the bonding state of the bonding material 7a is good or not by the appearance inspection. In particular, when the electronic components 2 and the like are mounted on an automatic device, the efficiency of the appearance inspection for inspecting the mounted state thereof can be greatly improved.

Next, if the protrusions 8 of the small-diameter barrier layer are formed in the regions adjacent to the heat dissipation through holes 15 so as to surround the heat dissipation through holes 15 , the protrusions 8 exhibit a waterproof effect. The reason for this is that the solder is less likely to wet the barrier layer than the heat sink 24 , the thermal diffusion plate 31 , and the upper conductor layer 12 , which have good wettability of the solder as the bonding material 7 a . Also, since the convex portion 8 surrounding the heat dissipation through hole 15 is not easily wetted by the solder, it is also possible to prevent the bonding material 7a as molten solder from flowing into the heat dissipation through hole 15 and flowing from one main surface 11a to the other. main surface 11b. In this way, not only can the short circuit due to the solder be suppressed as described above, but the hole portion as the heat dissipation through hole 15 can be left as it is, and the auxiliary material contained in the bonding material 7 a can be smoothly discharged from the heat dissipation through hole 15 to the outside. Flux gas. Therefore, it is possible to suppress the remaining of voids due to the flux gas in the bonding material 7a.

In addition, the convex portion 8 may be formed not only adjacent to the heat dissipation through hole 15 but also at any position between the heat dissipation plate 24 and the heat diffusion plate 31 and the upper conductor layer 12 , for example. Thereby, the mounting height with respect to the printed circuit board 1 of the electronic component 2 and the thermal diffusion part 3 mounted on the printed circuit board 1 can be kept constant. In addition, by providing the convex parts 8 as symbols at the four corners of the region where the electronic components 2 and the thermal diffusion part 3 are mounted from the perspective of transmission from one of the main surfaces 11 a of the printed circuit board 1 , the respective main surfaces and the printed circuit board 1 can be aligned with each other. The electronic components 2 and the thermal diffusion plate 31 are arranged and mounted so that the upper conductor layers 12 are substantially parallel to each other.

Embodiment 3.

17 is a schematic cross-sectional view of a portion taken along line A-A of FIG. 15 in Embodiment 3. FIG. Referring to FIG. 17 , the semiconductor device 301 of the present embodiment has basically the same structure as the semiconductor device 101, and therefore the same components are assigned the same reference numerals and the description thereof will not be repeated. However, in the semiconductor device 301 , at least a part of the plurality of first heat dissipation through holes 15 a overlapping the electronic component 2 via the conductor layers 12 , 13 , and 14 and the second heat dissipation through holes 15 b overlapping the thermal diffusion plate 31 Inside, the bonding material 7a is arranged in an amount equal to or more than 1/3 of the volume of the inside. However, the bonding material 7a may be similarly disposed inside the second heat dissipation through hole 15b (see FIG. 15 ) that does not overlap with either the electronic component 2 or the thermal diffusion plate 31 . In this point, the semiconductor device 301 is different from the semiconductor device 101 in which the conductive material other than the conductor film 15c on the inner wall surface is not arranged in the hole portion such as the first heat dissipation through hole 15a.

18 to 21 are schematic cross-sectional views showing modes in each manufacturing process of the semiconductor device 301 of the present embodiment. Next, the outline of the manufacturing method of the semiconductor device 301 will be described with reference to FIGS. 18 to 21 , especially focusing on the mounting process of the electronic component 2 and the thermal diffusion portion 3 .

Referring to FIG. 18 , on the upper conductor layer 12 of the printed circuit board 1, a solder plate 6b is arranged via a flux for removing the oxide film of the solder. The solder plate 6b is placed so as to cover the heat dissipation through hole 15 from directly above. In addition, a heat-resistant tape 6c such as polyimide is pasted on the lower conductor layer 13 (the lower side in the figure) in a part of the first region and the second region of the printed circuit board 1 . The heat-resistant tape 6c is affixed so that the hole part of the through-hole 15 for heat dissipation may be blocked especially from the other main surface 11b side.

Referring to FIG. 19, the electronic component 2 is mounted on the solder plate 6b, and a generally known heat reflow process is performed in this state. As a result, referring to FIG. 20 , the portion where the solder plate 6 b is melted and becomes the bonding material 7 b flows along the surface of the upper conductor layer 12 , and fills the inside of the heat dissipation through hole 15 . The reason for this is that the solder plate 6 b is arranged so as to cover the hole portion of the heat dissipation through hole 15 . In addition, since the heat-resistant tape 6c is attached to the lower conductor layer 13 in the first and second regions, the portion formed by melting the solder plate 6b does not leak to the lower side of the heat-resistant tape 6c, but is filled for heat dissipation. inside the through hole 15 .

In addition, although the entire inside of the heat dissipation through hole 15 may be filled with the bonding material 7a, as shown in FIG.

Referring to FIG. 21 , after the solder in the heat dissipation through hole 15 is cured, the heat-resistant tape 6c is removed. Then, similarly to the process of FIG. 8 , for example, the heat dissipation member 41 and the cooling body 42 are arranged in order from the upper side to the lower side so as to be in contact with the lower conductor layer 13 of the printed circuit board 1 so as to be in close contact with each other.

Next, the effects of the present embodiment will be described. In addition to the same effects as those of Embodiment 1, the present embodiment has the following functions and effects.

By arranging the bonding material 7a inside the heat dissipation through hole 15 as in the semiconductor device 301, the heat generated by the electronic component 2 can be increased inside the first heat dissipation through hole 15a and the second heat dissipation through hole 15b heat transfer to the thermal diffusion plate 31 side. This is because, as described above, conductive members such as solder have higher thermal conductivity than hollow ones, so the insides of the first heat dissipation through holes 15 a and the like are filled with solder, so that the first heat dissipation through holes 15 a and the first heat dissipation through holes 15 a have higher thermal conductivity. The area of the region in which higher heat conduction can be achieved in the cross section where the extending directions intersect increases in area.

When the printed circuit board 1 is heated in the above-mentioned thermal reflow process, if the solder plate 6b is melted before the conductor film 15c on the inner wall surface of the heat-dissipating through hole 15, the melted solder does not easily flow along the heat-dissipating through hole 15. flow on the inner wall. As a result, the molten solder becomes a lump of solder, and the inside of the heat dissipation through hole 15 is closed, and as shown in FIG. 20 , FIG. 21 and FIG. When the amount of supplied solder is small, the ratio of the solder arranged in the heat dissipation through hole 15 becomes smaller.

However, even in the form of FIGS. 20 , 21 , and 17 , in at least the portion of the solder bump 71 of the bonding material 7 a adjacent to the upper conductor layer 12 and the lower conductor layer 13 , the portion of the heat dissipation through hole 15 is Since the cross section intersecting with the extending direction is filled with the bulk solder 71, the ratio of the solder with high thermal conductivity in the cross-sectional area is increased. Therefore, the heat dissipation performance can be improved compared to the case where the inside of the heat dissipation through hole 15 is not filled with solder at all, for example, as in the semiconductor device 101 . Such an effect of improving heat dissipation can be sufficiently obtained if the bump 71 extending from the upper conductor layer 12 side has a height h equal to or more than 1/3 of the length in the extending direction of the heat dissipation through hole 15 . When the solder bump 71 extends only from either the upper conductor layer 12 side or the lower conductor layer 13 side, or the bump solder 71 extends from both the upper conductor layer 12 side and the lower conductor layer 13 side The same is true in the case of . That is, it is preferable to fill the plurality of through holes 15 for heat dissipation, which are blocked by at least one (upper side) main surface of the thermal diffusion plate 31, by a volume equal to or more than 1/3 of the volume of the through holes 15 for heat dissipation. way, there is solder.

Furthermore, in Embodiment 2, the protrusions 8 prevent the bonding material 7 a from flowing into the heat dissipation through holes 15 , thereby reducing the possibility of short-circuiting the upper conductor layer 12 and the cooling body 42 directly below it. On the other hand, in the present embodiment, the bonding material 7 a is actively flowed into the heat dissipation through hole 15 . However, in the present embodiment, the bonding material 7a flows into the heat dissipation through hole in a state where the heat-resistant tape 6c is affixed in advance so as to block the hole portion of the heat dissipation through hole 15 from the other main surface 11b side. within 15. The heat-resistant tape 6c is removed after the solder in the heat dissipation through hole 15 is cured. The heat-resistant tape 6c closes the hole and prevents the bonding material 7a from flowing into the cooling body 42 from the heat dissipation through hole 15, so that the short-circuit problem described above can be avoided also in this embodiment.

Embodiment 4.

22 is a schematic cross-sectional view of a portion taken along the line A-A in FIG. 15 in Embodiment 4. FIG. FIG. 23 is a schematic cross-sectional view of a portion taken along line B-B of FIG. 15 in Embodiment 4. FIG. Referring to FIGS. 22 and 23 , the semiconductor device 401 of the present embodiment has basically the same structure as the semiconductor device 101 , and therefore the same components are assigned the same reference numerals and the description thereof will not be repeated. However, in the semiconductor device 401 , the thermal diffusion plate 31 serving as the thermal diffusion part 3 includes two parts, the first thermal diffusion plate part 31 a (first part) and the second thermal diffusion plate part 31 b (second part) . The first thermal diffusion plate portion 31a is a portion that extends in a direction along one main surface 11a of the printed circuit board 1 and is joined to the one main surface 11a, and extends in the left-right direction in FIGS. 22 and 23 . The second thermal diffusion plate portion 31b is connected to the first thermal diffusion plate portion 31a, and extends in a direction intersecting with the first thermal diffusion plate portion, that is, upward in FIGS. 22 and 23 . Therefore, the second thermal diffusion plate portion 31b is not bonded to the printed circuit board 1 .

In the cross-sectional views of FIGS. 22 and 23 , the boundary portion between the first thermal diffusion plate portion 31a and the second thermal diffusion plate portion 31b is bent so that the extending direction thereof is changed by about 90°. However, not limited to this, for example, the angle formed by the extending directions of the first thermal diffusion plate portion 31a and the second thermal diffusion plate portion 31b may be less than 90° or may exceed 90°. That is, in the thermal diffusion plate 31 of the semiconductor device 401, only a part of the region is joined to one of the main surfaces 11a. In this point, the semiconductor device 401 is different from the semiconductor device 101 which does not have such two parts and the entirety is bonded to one main surface 11 a of the printed circuit board 1 .

In addition, in FIGS. 22 and 23, the convex part 8 is provided similarly to Embodiment 2, but this convex part 8 may not be formed. This is also the same in each of the following embodiments.

The thermal diffusion plate 31 of the present embodiment may be, for example, a finned heat sink suitable for air cooling. As for the heat sink, it is a common practice to build and use it so as to extend in the vertical direction together with lead parts such as TO-220, but in this embodiment, it can also be used horizontally so as to extend in the horizontal direction. . In addition, if a general-purpose heat sink is used for the thermal diffusion plate 31, the manufacturing cost can be reduced.

Next, the effects of the present embodiment will be described. In addition to the same effects as those of Embodiment 1, the present embodiment has the following functions and effects.

When the thermal diffusion plate 31 has the second thermal diffusion plate portion 31b, not only the thermal diffusion effect but also the heat dissipation effect is enhanced. That is, the first thermal diffusion plate portion 31a bonded to the printed circuit board 1 has the effect of thermal diffusion, and the second thermal diffusion plate portion 31b whose entire surface is in contact with the outside air has the effect of heat dissipation. Therefore, the effect of releasing the heat generated by the electronic component 2 to the outside can be further enhanced compared to the first embodiment and the like.

In addition, when the electronic component 2 is a switching element such as a MOSFET, radiation noise is output during switching, but the radiation noise to the outside can be reduced by the second thermal diffusion plate portion 31b of the thermal diffusion plate 31 . In addition, when the electronic component 2 is, for example, a control IC, an IC that processes minute signals, or the like, there is an effect of reducing radiation noise from the outside, and malfunction of the IC can be prevented. In addition, the second thermal diffusion plate portion 31b of the thermal diffusion plate 31 has a dust-proof effect such as dust from the outside. The second thermal diffusion plate portion 31b of the thermal diffusion plate 31 absorbs the stress applied to the printed circuit board 1, so that the printed circuit board 1 is not easily warped, and the strength of the printed circuit board 1 is increased. In addition, since the thermal diffusion plate 31 has the second thermal diffusion plate portion 31b, the thermal cycle property of the bonding material 7a can also be improved, so that the reliability of the semiconductor device 401 is improved.

Embodiment 5.

24 is a schematic cross-sectional view of a portion taken along the line A-A in FIG. 15 in the first example of Embodiment 5. FIG. 25 is a schematic cross-sectional view of a portion taken along the line A-A in FIG. 15 in the second example of Embodiment 5. FIG. Referring to FIGS. 24 and 25 , the semiconductor device 501 of the first example and the semiconductor device 502 of the second example of the present embodiment have basically the same structure as the semiconductor device 101 , so the same components are assigned the same reference numerals without repeating them. illustrate. However, in the semiconductor devices 501 and 502, the heat sink 24 of the electronic component 2, in particular, has the horizontally extending portion 24c (third portion) and a vertically extending portion 24d (fourth portion) that is a portion (surface) extending in the vertical direction intersecting with the one main surface 11a. Furthermore, the thermal diffusion plate 31 is joined to both at least a part of the horizontally extending part 24c and at least a part of the vertically extending part 24d by the joining material 7a.

That is, in the semiconductor device 501, for example, the thermal diffusion plate 31 includes the first thermal diffusion plate portion 31a joined to the printed circuit board 1 as in the fourth embodiment, and the thermal diffusion plate portion 31a extending in the direction along one main surface 11a as in the fourth embodiment. There are three parts: the third thermal diffusion plate part 31c, which is a part, and the fourth thermal diffusion plate part 31d, which is a part extending in the vertical direction intersecting with one main surface 11a. These are connected in the order of the 1st thermal diffusion plate part 31a, the 4th thermal diffusion plate part 31d, and the 3rd thermal diffusion plate part 31c from the right side of the figure to the left side.

In the semiconductor device 501, the first thermal diffusion plate portion 31a is bonded to the upper conductor layer 12, whereas the third thermal diffusion plate portion 31c and the fourth thermal diffusion plate portion 31d are provided to be mounted thereon to dissipate heat. The shape of the way curved on the surface of the plate 24 . The third thermal diffusion plate portion 31c overlaps with the horizontally extending portion 24c in a plan view, and the fourth thermal diffusion plate portion 31d is arranged so as to face the vertically extending portion 24d in a plan view.

The semiconductor device 502 has basically the same structure as the semiconductor device 501 , but is slightly different in the cross-sectional shape of the thermal diffusion plate 31 . Specifically, the thermal diffusion plate 31 has the thermal diffusion plate portions 31 a , 31 c , and 31 d similarly to the semiconductor device 501 . The first thermal diffusion plate portion 31 a of the semiconductor device 502 is bonded to the upper conductor layer 12 but is slightly thicker than the first thermal diffusion plate portion 31 a of the semiconductor device 501 . The thermal diffusion plate 31 partially has a cutout on the left side of the drawing, and the third thermal diffusion plate portion 31c and the fourth thermal diffusion plate portion 31d are formed by the cutout. Here, the portion including the surface of the cutout extending along one main surface 11a so as to face the horizontally extending portion 24c is referred to as the third thermal diffusion plate portion 31c, and the portion including the surface facing the vertically extending portion 24d will be referred to as the third thermal diffusion plate portion 31c. The portion of the surface of the cutout extending in the direction intersecting with one of the main surfaces 11a in such a manner is referred to as the fourth thermal diffusion plate portion 31d. As a result, in the semiconductor device 502, the third thermal diffusion plate portion 31c is also overlapped so as to be mounted on the horizontally extending portion 24c.

As described above, in the present embodiment, the heat dissipation plate 24 of the electronic component 2 and the thermal diffusion plate 31 of the thermal diffusion part 3 are joined on two surfaces. In this point, the present embodiment is different from the semiconductor device 101 in which the heat dissipation plate 24 and the thermal diffusion plate 31 are joined on one surface. In addition, in the present embodiment, the heat dissipation plate 24 and the thermal diffusion plate 31 may be joined on three or more surfaces.

In the manufacturing method of the present embodiment, the shape of the thermal diffusion plate 31 in the semiconductor device 501 can be formed at a low manufacturing cost by, for example, subjecting a copper plate to a generally known press working. In addition, the shape of the thermal diffusion plate 31 in the semiconductor device 502 is obtained by forming a notch by, for example, performing a generally known chipping process or extrusion process on a copper plate. In this case, the thermal resistance between the electronic component 2 and the thermal diffusion plate 31 can be reduced, and the thermal diffusion efficiency of the thermal diffusion plate 31 can be further improved.

Next, with reference to FIG. 26 , the effects of the present embodiment will be described. In addition to the same effects as those of Embodiment 1, the present embodiment has the following functions and effects.

By having the structure of this embodiment, the joint thermal resistance between the heat dissipation plate 24 and the thermal diffusion plate 31 can be reduced, and the thermal diffusion effect can be enhanced. In addition, with the above configuration, the stress applied to the printed circuit board 1 is easily absorbed, and the printed circuit board 1 is less likely to warp, so that the strength of the printed circuit board 1 increases. In addition, since the thermal cycleability of the bonding material 7a can also be improved, the reliability of the semiconductor device 401 is improved.

In FIG. 24, in the boundary portion of the first thermal diffusion plate portion 31a and the fourth thermal diffusion plate portion 31d and the boundary portion of the fourth thermal diffusion plate portion 31d and the third thermal diffusion plate portion 31c, the extending direction is Change the way to bend about 90°. However, it is not limited to this, and the angle formed by the extending directions of the two parts sandwiched between these boundary portions may be smaller than 90° or may exceed 90°. For example, FIG. 26 shows a more preferred way of the region XXVI enclosed by the dotted line in FIG. 24 . Referring to FIG. 26 , the angle formed by the third thermal diffusion plate portion 31c and the fourth thermal diffusion plate portion 31d here exceeds 90°. Thereby, the air in the region between the third thermal diffusion plate portion 31c and the horizontally extending portion 24c can be easily removed. Thereby, the air layer between the two becomes thin, and the thermal conductivity between the two becomes high. From the viewpoint of easy removal of air in the area between the third thermal diffusion plate portion 31c and the horizontally extending portion 24c, it is preferable to make the two as close as possible or to make the extending direction of the third thermal diffusion plate portion 31c opposite to each other as described above. It is inclined in the direction of one main surface 11a.

Embodiment 6.

FIG. 27 shows the whole or a part of the semiconductor device of each example of Embodiment 6 in a plan view from the upper perspective, that is, from the perspective of transmission from above. 28 is a schematic cross-sectional view of a portion taken along line C-C in FIG. 27 in the first example of Embodiment 6. FIG. 29 is a schematic cross-sectional view of a portion taken along line C-C in FIG. 27 in the second example of Embodiment 6. FIG. 28 and 29 are schematic cross-sectional views viewed from the direction corresponding to the line B-B in FIG. 15 . 27 , 28 , and 29 , the semiconductor device 601 of the first example and the semiconductor device 602 of the second example of the present embodiment have basically the same structure as the semiconductor device 101 , and therefore the same components are assigned the same reference numerals. Its description is not repeated. However, in the semiconductor devices 601 and 602, for example, the lower facing mold surface 23e (first surface) of the resin mold portion 23 of the electronic component 2, which faces one main surface 11a of the printed circuit board 1, and the opposite side thereof are considered. The upper face faces the molding surface 23f (second surface). At this time, a part of the thermal diffusion plate 31 is arranged so as to cover the upper facing molding surface 23f.

That is, in the semiconductor device 601, for example, the thermal diffusion plate 31 includes the first thermal diffusion plate portion 31a joined to the printed circuit board 1 as in the fourth and fifth embodiments, and the same as the first thermal diffusion plate portion 31a in the direction along one main surface 11a. There are three parts: the fifth thermal diffusion plate part 31f which is the extended part, and the sixth thermal diffusion plate part 31g which is a part which is extended in the vertical direction intersecting with the one main surface 11a. From the left side to the right side of the figure, they are arranged according to the first thermal diffusion plate portion 31a, the sixth thermal diffusion plate portion 31g, the fifth thermal diffusion plate portion 31f, the sixth thermal diffusion plate portion 31g, and the first thermal diffusion plate portion 31a sequential connection.

In the semiconductor device 601, the first thermal diffusion plate portion 31a is bonded to the upper conductor layer 12, whereas the fifth thermal diffusion plate portion 31f and the sixth thermal diffusion plate portion 31g are provided so as to span from the upper side therefrom. The shape of the resin-molded portion 23 is curved. Further, the fifth thermal diffusion plate portion 31f overlaps with the upper-facing mold surface 23f in plan view, and the sixth thermal diffusion plate portion 31g faces the mold side surface 23g of the resin mold portion 23 configuration.

The semiconductor device 602 has basically the same structure as the semiconductor device 601 , but is slightly different in the cross-sectional shape of the thermal diffusion plate 31 . Specifically, the thermal diffusion plate 31 has the thermal diffusion plate portions 31 a , 31 g , and 31 f similarly to the semiconductor device 601 . In the semiconductor device 602, the first thermal diffusion plate portion 31a joined to one main surface 11a extends directly upward, but the portion extending directly upward becomes the sixth thermal diffusion plate portion 31g and faces the mold side surface 23g. Here, the part that spreads in the direction intersecting with the one main surface 11a so as to face the mold side surface 23g is referred to as the sixth thermal diffusion plate part 31g, and the part corresponding to the lowermost part of the sixth thermal diffusion plate part 31g is referred to as the sixth thermal diffusion plate part 31g. The area where the printed circuit board 1 is joined is referred to as the first thermal diffusion plate portion 31a. As a result, in the semiconductor device 602, the fifth thermal diffusion plate portion 31f and the sixth thermal diffusion plate portion 31g also have shapes bent so as to span the resin mold portion 23 from the upper side therefrom.

As described above, in the present embodiment, the thermal diffusion plate 31 is joined to the printed circuit board 1 so as to straddle the electronic component 2 . The thermal diffusion plate 31 includes a region arranged so as to cover and overlap the upper surface of the electronic component 2 . In this point, the present embodiment is different from the semiconductor device 101 which does not have such a structure. In addition, the fifth thermal diffusion plate portion 31f of the thermal diffusion plate 31 may be joined to the upper facing mold surface 23f.

In the manufacturing method of the present embodiment, the shape of the thermal diffusion plate 31 in the semiconductor device 601 can be formed in the same manner as the above-described semiconductor device 501 . In addition, the shape of the thermal diffusion plate 31 in the semiconductor device 602 can be formed in the same manner as the above-described semiconductor device 502 .

The effect of this embodiment is as follows. Since the thermal diffusion plate 31 has the thermal diffusion plate portions 31f and 31g as in the present embodiment, in addition to the same effects as those of the first embodiment, the same effects as those of the fourth embodiment are also obtained. Therefore, the detailed description thereof will not be repeated here. 28 and 29, an air layer is provided between the thermal diffusion plate 31 and the resin mold portion 23, but when the two are joined without the air layer, the thermal conductivity between the two is higher. high.

Embodiment 7.

FIG. 30 shows an enlarged region of the semiconductor device according to the seventh embodiment, particularly a part of the printed circuit board 1 . FIG. 31 shows a further enlarged view of the region XXXI surrounded by the dotted line in FIG. 30 , that is, the mode of the insulating layer 11 . Referring to FIGS. 30 and 31 , the semiconductor device 701 of the present embodiment has basically the same structure as the semiconductor device 101 , and therefore the same components are denoted by the same reference numerals and the description thereof will not be repeated. However, the semiconductor device 701 is different from the semiconductor device 101 in that the insulating layer 11 of the printed circuit board 1 has the filler 16 . Furthermore, as shown in FIG. 31 , the insulating layer 11 contains glass fiber 17 and epoxy resin 18 .

The filler 16 is an inorganic filler particle, and alumina particles are preferably used, but the filler 16 is not limited to this, and may be ceramic particles such as aluminum nitride or boron nitride. In addition, the filler 16 may be a structure in which several kinds of particles are mixed, or a structure in which aluminum hydroxide is mixed with alumina, for example.

That is, in the semiconductor device 701 , each of the plurality of insulating layers 11 included in the printed circuit board 1 includes inorganic filler particles. Thereby, the thermal conductivity and heat resistance of the insulating layer 11 can be improved. By including the filler 16 as inorganic filler particles in the insulating layer 11 , heat can be conducted via the filler 16 . Therefore, the thermal conduction of the insulating layer 11 can be increased, and the thermal resistance of the printed circuit board 1 can be reduced.

For the semiconductor device 701 having the printed circuit board 1 including the insulating layer 11 containing the filler 16 of alumina at 70% by weight, the thermal resistance value was simulated using the formula (1) and the same model as that of the first embodiment. In addition, this model has completely the same dimensions and structure as the model of the semiconductor device 101 of the first embodiment except for the presence or absence of the above-mentioned filler 16 . As a result, it was found that the thermal resistance value can be further reduced by about 5% compared to the example of the semiconductor device 101 of FIG. 11 .

In addition, in this embodiment, in order to increase the effect of heat dissipation, it is important to increase the packing density of the filler 16 contained in the insulating layer 11 . Specifically, it is more preferable to increase the packing density of the filler 16 to 80% by weight. Therefore, the shape of the filler 16 is not limited to a nearly spherical shape as shown in FIG. 13(B) , and may be a three-dimensional shape based on a polygon such as a tetrahedron or a hexagonal crystal.

Furthermore, in this embodiment, the size of the filler 16 filled in the insulating layer 11 may not be constant. That is, even when the insulating layer 11 contains only a single type of particles of the filler 16 , the filler 16 may be constituted by mixing particles of several sizes. In this case, since the particles of the filler 16 having a small size enter the region sandwiched between the particles of the filler 16 having a large size, the filler 16 can be filled with a higher density. Therefore, the heat dissipation of the insulating layer 11 can be further improved.

Embodiment 8.

In FIG. 32, the area|region of the 1st heat dissipation through hole 15a especially of the semiconductor device of Embodiment 8 is enlarged, and its planar form is shown. FIG. 33 is a schematic cross-sectional view of a portion taken along line XXXIII-XXXIII of FIG. 32 . Referring to FIGS. 32 and 33 , the semiconductor device 801 of the present embodiment has basically the same structure as the semiconductor device 101 , and therefore the same components are assigned the same reference numerals and the description thereof will not be repeated. However, in the semiconductor device 801, in the region sandwiched between a plurality of (especially a pair) adjacent first heat dissipation through holes 15a in the upper conductor layer 12, the first heat dissipation through holes 15a A groove 15d is formed so that the hole portions of the hole 15a are connected to each other. In this point, the semiconductor device 801 is different from the semiconductor device 101 in which such a groove 15d is not formed.

In addition, in FIGS. 32 and 33 , the grooves 15d are formed only in the first region, but the present invention is not limited to this, and the second region may also connect the holes of the heat dissipation through holes 15 adjacent to each other. Grooves 15d are formed. In other words, the printed circuit board 1 of the semiconductor device 801 is formed with a plurality of heat dissipation through holes 15 , which connect the heat dissipation through holes 15 adjacent to each other in the transmission viewpoint from one main surface 11 a of the printed circuit board 1 to each other. Slot 15d.

In addition, when patterning the upper conductor layer 12 of the printed circuit board 1, the above-mentioned groove 15d can be formed by a usual photolithography technique and etching.

By providing the grooves 15d as described above, in the semiconductor device 801, the expanded air in the first heat dissipation through holes 15a can be released to the outside through the grooves 15d by heating for melting the solder during its manufacture. Therefore, by suppressing the increase of the pressure in the first heat dissipation through hole 15a, the filling of the solder can be easily realized.

Embodiment 9.

FIG. 34 shows the whole or a part of the semiconductor device according to the ninth embodiment, as viewed from above. Referring to FIG. 34 , the semiconductor device 901 according to the present embodiment has basically the same structure as the semiconductor device 101, and therefore the same components are denoted by the same reference numerals and the description thereof will not be repeated. However, in the semiconductor device 901, the thermal diffusion plate 31 arranged around the electronic component 2 from the perspective of transmission from one main surface 11a of the printed circuit board 1 is divided into three thermal diffusion plates 31x, 31y, and 31z. These thermal diffusion plates 31x, 31y, and 31z are preferably arranged at intervals from each other, but are not limited to this. In this point, the semiconductor device 901 is different from the semiconductor device 101 in which the thermal diffusion plate 31 has a single structure and is arranged on the three-directional sides around the electronic component 2 .

In FIG. 34, as an example, the thermal diffusion plate 31 is divided into three regions spaced apart from each other. However, the thermal diffusion plate 31 may be divided into any number of regions other than three, for example, two or four. Each of the plurality of thermal diffusion plates 31x, 31y, and 31z is joined to the electronic component 2 by solder as the joining material 7a.

For example, when the size of the thermal diffusion plate 31 of the semiconductor device 101 becomes large, it is difficult to mount it with a chip mounter. In addition, when the thermal diffusion plate 31 has a rectangular or square planar shape with the center and the center of gravity at the same point, compared with the case where the thermal diffusion plate 31 has an asymmetrical planar shape, the defect rate of the mounting process by the chip mounter reduce. Therefore, as described in the present embodiment, by dividing the thermal diffusion plate 31 into a plurality of rectangles and arranging them, the thermal diffusion plate 31 can be easily mounted by a chip mounter, and the mounting cost can be reduced. That is, according to the present embodiment, the thermal diffusion plate 31 can be made into a form suitable for automatic mounting.

Embodiment 10.

FIG. 35 shows the whole or part of the semiconductor device according to the first example of the tenth embodiment, as viewed from above. In addition, FIG. 36 is a view of the whole or a part of the semiconductor device of the second example of the tenth embodiment viewed from above. 35 and 36 , the semiconductor device 1001 according to the present embodiment and the semiconductor device 1002 of the second example have basically the same structure as the semiconductor device 101, so the same components are denoted by the same reference numerals and the description thereof will not be repeated. However, in the semiconductor devices 1001 and 1002 , the electronic components 2 are all arranged as four electronic components 2 a , 2 b , 2 c , and 2 d at a distance from each other from a transmission viewpoint from one main surface 11 a of the printed circuit board 1 . In the semiconductor device 1001, four electronic components 2a to 2d are arranged in one row in the left-right direction of the drawing, whereas in the semiconductor device 1002, there are two rows in the left-right direction in the drawing, and in the The vertical direction becomes two columns, and the four electronic components 2a to 2d are arranged in a matrix.

As described above, in the semiconductor device of the present embodiment, the plurality of electronic components 2 are arranged at intervals. In this point, the present embodiment is different from the semiconductor device 101 in which only a single electronic component 2 is arranged. In addition, the number of the arrangement|positioning electronic components 2 is not limited to the four shown by the semiconductor devices 1001 and 1002, It may be arbitrary multiple. Moreover, the thermal-diffusion plate 31 connected as a single thermal-diffusion part 3 is arrange|positioned at the periphery of each of several electronic components 2a-2d in planar view.

Next, the effects of the present embodiment will be described with reference to FIGS. 37 and 38 as comparative examples.

FIG. 37 shows the whole or a part of the semiconductor device of the comparative example with respect to the first example of the tenth embodiment, as viewed from above. In addition, FIG. 38 shows an aspect of the semiconductor device of the whole or a part of the semiconductor device of the comparative example of the second example of Embodiment 11 from a transmissive viewpoint from above. 37 and 38 , the semiconductor device 1003 and the semiconductor device 1004 have basically the same structure as the semiconductor devices 1001 and 1002, so the same components are denoted by the same reference numerals and the description thereof will not be repeated.

However, in the semiconductor devices 1003 and 1004, as in the semiconductor device 901 of the ninth embodiment, the thermal diffusion plate 31 is divided into a plurality of thermal diffusion plates. Specifically, in FIG. 37 , the thermal diffusion plate 31 is divided into a thermal diffusion plate 31x on the upper side of the electronic component 2, and is sandwiched between the electronic components 2a to 2d with respect to the left-right direction of the drawing (with the electronic components 2a and 2d). adjacent) five thermal diffusion plates 31y. In addition, in FIG. 38 , the thermal diffusion plate 31 is divided into a thermal diffusion plate 31x extending in the center portion in the vertical direction of the figure, and three adjacent to the electronic components 2a and 2b in the area on the upper side of the thermal diffusion plate 31x. The thermal diffusion plate 31y and the three thermal diffusion plates 31z adjacent to the electronic components 2c and 2d in the region below the thermal diffusion plate 31x.

For example, when a plurality of electronic components 2 are connected in parallel in one semiconductor device as shown in FIG. 38 , there is a possibility that the amount of heat generation varies due to variations in the internal resistance of the electronic components 2 and the like. For example, when four thermal diffusion plates are arranged for each of the plurality of electronic components 2a to 2d in parallel connection, the electronic component with a large amount of heat may increase its temperature due to its own heat generation and further increase the amount of heat generated. Possibility of thermal runaway. As shown in FIG. 37 , the same applies to the case where a plurality of electronic components 2 are connected in parallel in one semiconductor device.

However, by arranging only a single thermal diffusion plate 31 of the plurality of electronic components 2a to 2d as described in this embodiment, the temperature of the respective electronic components 2a to 2d is balanced, and a highly reliable semiconductor device that is less prone to thermal runaway can be provided. The reason for this is that, by arranging only one thermal diffusion plate 31 for each of the plurality of electronic components 2a to 2d, the thermal diffusion plate 31 can be arranged from a plurality of electronic components 2a to 2d. The heat dissipation to the same thermal diffusion plate 31 for each of the electronic components 2a to 2d is more uniform.

Embodiment 11.

39 is a schematic cross-sectional view of a portion taken along line C-C in FIG. 27 in the first example of Embodiment 11. FIG. 40 is a schematic cross-sectional view of a portion taken along the line A-A in FIG. 15 in the second example of the eleventh embodiment. 41 is a schematic cross-sectional view of a portion taken along the line A-A in FIG. 15 in the third example of the eleventh embodiment.

39 , the semiconductor device 1101 of the first example of the present embodiment is arranged such that the housing 51 is in close contact with the fifth thermal diffusion plate portion 31f of the thermal diffusion plate 31 of the semiconductor device 601 of the sixth embodiment. 40 , the semiconductor device 1102 of the second example of the present embodiment is arranged such that the housing 51 is in close contact with the third thermal diffusion plate portion 31c and the fourth thermal diffusion plate portion of the thermal diffusion plate 31 of the semiconductor device 502 of the fifth embodiment 31d. 41 , the semiconductor device 1103 of the third example of the present embodiment is arranged such that the housing 51 is in close contact with the second thermal diffusion plate portion 31b of the thermal diffusion plate 31 of the semiconductor device 401 of the fourth embodiment. This embodiment differs from the semiconductor devices 601 , 502 , and 401 in which the housing 51 is arranged in this way, but is basically the same in other points. Therefore, in the present embodiment, the same reference numerals are assigned to the same components as those of the semiconductor device described, and the description thereof will not be repeated.

The housing 51 is a member that protects the entire semiconductor devices 1101 to 1103 from the outside, and a part thereof, for example, a flat plate-shaped portion is shown in FIGS. 39 to 41 . The frame body 51 is preferably formed of aluminum. This is because aluminum can transfer heat from the inside of the semiconductor device to the outside, and aluminum is lighter than copper or the like. In addition, the frame body 51 may be formed of a ceramic material having good thermal conductivity, such as aluminum oxide or aluminum nitride, on which a metal film of copper or the like is formed. Furthermore, the frame body 51 may be formed of a metal material in which a nickel-plated film and a gold-plated film are formed on the surface of an arbitrary alloy material selected from the group consisting of copper alloy, aluminum alloy, and magnesium alloy. By using such a material with good thermal conductivity as the housing 51 , the thermal conductivity (heat dissipation) of the semiconductor devices 1101 to 1103 can be improved.

In addition, in the thermal diffusion plate 31 of the semiconductor device according to each of the embodiments (examples) not listed here, the frame body 51 may be arranged in close contact with each other in the same manner as described above.

In the present embodiment, in addition to the route of the first embodiment in which the heat generated by the electronic component 2 is dissipated from the thermal diffusion plate 31 of FIG. 10 to the heat dissipation portion 4 side via the second heat dissipation through holes 15b, the thermal diffusion plate is 31 is a route for dissipating heat to the outside via the casing 51 . Therefore, the semiconductor devices 1101 to 1103 having better heat dissipation properties can be provided as compared with the structure without the frame body 51 .

42 is a schematic cross-sectional view of a portion taken along the line C-C in FIG. 27 in the fourth example of the eleventh embodiment. 42 , the semiconductor device 1104 of the fourth example of the present embodiment is arranged so that the heat dissipation member 52 is sandwiched between the thermal diffusion plate 31 (the fifth heat diffusion plate portion 31f ) and the housing 51 of the semiconductor device 1101 . 52 is in close contact with both the thermal diffusion plate 31 and the frame body 51 . The heat dissipation member 52 is preferably a sheet-like member formed of the same material as the heat dissipation member 41 . In this point, the semiconductor device 1104 is different from the semiconductor device 1101 without the heat dissipation member 52, but the other points are basically the same. Therefore, in the present embodiment, the same components as those of the semiconductor device 1101 are denoted by the same reference numerals, and the description thereof will not be repeated. When the potentials of the thermal diffusion plate 31 and the frame body 51 are different, it is preferable to sandwich the heat dissipation member 52 having electrical insulating properties therebetween. Thereby, while preventing the short circuit between the thermal diffusion plate 31 and the casing 51 , the heat generated by the electronic component 2 can be more efficiently dissipated from the thermal diffusion plate 31 and the casing 51 to the outside thereof.

Embodiment 12.

43 is a schematic plan view of a semiconductor device according to each example of the twelfth embodiment. 44 is a schematic cross-sectional view of a portion taken along the line A-A in FIG. 43 in the first example of the twelfth embodiment. 45 is a schematic cross-sectional view of a portion taken along the line B-B in FIG. 43 in the second example of the twelfth embodiment. Referring to FIGS. 43 to 44 , the semiconductor device 1201 shown in these figures has basically the same structure as that of FIGS. 15 and 16 , and therefore the same components are denoted by the same reference numerals and the description thereof will not be repeated. However, in the semiconductor device 1201 , the thermal diffusion material 60 is provided so as to cover at least a part of the electronic component 2 and the thermal diffusion part 3 .

As the thermal diffusion material 60 , it is preferable to use a material excellent in electrical properties and mechanical properties, and excellent in heat dissipating properties at a portion having high thermal conductivity and high calorific value. In addition, the thermal diffusion material 60 is preferably a material having a low coefficient of thermal expansion, excellent crack resistance, low viscosity, and good workability. The thermal diffusion material 60 is preferably a material that reduces the amount of warpage of the printed circuit board 1 and the like by reducing the stress during heat curing. In addition, it is preferable that the thermal diffusion material 60 has a small amount of weight loss under high temperature storage and is excellent in heat resistance. Furthermore, the thermal diffusion material 60 is preferably a material with a low impurity ion concentration and excellent reliability. From the above viewpoints, an epoxy-based potting material is used as a representative example of the thermal diffusion material 60 . However, the thermal diffusion material 60 may be any material selected from the group consisting of acrylic resin, silicon, urethane, urethane, epoxy resin, and fluorine. Furthermore, as the thermal diffusion material 60 , any of grease, adhesive, or heat sink may be used instead of the above-mentioned materials. However, the thermal diffusion material 60 is not limited to the above.

Referring to FIG. 45 , the semiconductor device 1202 of the second example of the present embodiment has basically the same structure as the semiconductor device 401 of FIG. 23 , and therefore the same components are denoted by the same reference numerals and the description thereof will not be repeated. However, the semiconductor device 1202 has the thermal diffusion material 60 so as to cover at least a part of the electronic component 2 and the thermal diffusion part 3 .

In FIG. 45 , the region surrounded by the second thermal diffusion plate portion 31 b of the thermal diffusion plate 31 is filled with the thermal diffusion material 60 . In other words, the thermal diffusion material 60 is formed so as to cover the first thermal diffusion plate portion 31 a and the electronic component 2 .

Next, the effects of the present embodiment will be described. In this embodiment, at least a part of the electronic component 2 and the thermal diffusion part 3 is covered with the thermal diffusion material 60 . Thereby, the heat generation from the electronic component 2 can be transmitted to the thermal diffusion part 3 more efficiently. In addition, heat dissipation by the thermal diffusion material 60 can also be improved. In addition, it is possible to obtain the effect of improving the external insulation, moisture resistance, water resistance, chlorine resistance, and oil resistance of the printed circuit board 1 and the electronic component 2 covered with the thermal diffusion material 60 . Furthermore, it is possible to suppress the contamination of foreign matter into the portions of the printed circuit board 1 and the electronic components 2 covered with the thermal diffusion material 60 .

Moreover, in the structure of FIG. 45, the thermal diffusion plate 31 has the 1st thermal diffusion plate part 31a and the 2nd thermal diffusion plate part 31b which differs by about 90 degrees with respect to this extending direction. Therefore, it is possible to prevent the thermal diffusion material 60 from flowing out to a region where the thermal diffusion material 60 is not intended to be supplied. In addition, in FIG. 45, a part or the whole of the electronic component 2 can be covered with the thermal diffusion material 60 of the minimum amount. In this way, in FIG. 45 , the electronic component 2 can be covered with the thermal diffusing material 60 by utilizing the characteristic of the shape of the thermal diffusing plate 31 . Thereby, high heat dissipation can be obtained at low cost.

In the above, as an example, an example in which the thermal diffusion material 60 is introduced into the structures of Embodiments 2 and 4 has been described. However, the thermal diffusion material 60 can be used in any of the above-mentioned examples of Embodiments 1 to 11.

It can also be applied in an appropriate combination of the features described in each of the above-described embodiments (each example included in the above) within a technically non-contradictory range.

It should be considered that the embodiment disclosed this time is merely an illustration in all points and is not limited thereto. The scope of the present invention is shown not by the above description but by the claims, and it is intended that the meanings equivalent to the claims and all modifications within the scope are included.

Claims (12)

1. A semiconductor device includes:

a printed substrate; and

an electronic component and a heat diffusion section bonded to one main surface of the printed board,

the electronic part and the heat diffusion portion are electrically and thermally connected by a bonding material,

the printed substrate includes: an insulating layer; a plurality of conductor layers disposed on the main surfaces of one and the other of the insulating layers; and a plurality of heat dissipation through holes penetrating from one main surface to the other main surface of the insulating layer,

at least a part of the plurality of heat dissipating through holes overlaps the electronic component at a transmission point of view from one main surface of the printed board, and at least another part of the plurality of heat dissipating through holes overlaps the heat diffusion portion at a transmission point of view from one main surface of the printed board,

at least a part of the plurality of heat dissipation through holes is arranged so as to overlap a heat dissipation portion in a transmission viewpoint from the other main surface of the printed substrate.

2. The semiconductor device according to claim 1,

a convex portion is disposed on one main surface of the printed board,

the electronic component and the heat diffusion portion are arranged so as to overlap the convex portion at a transmission point of view from one main surface of the printed board.

3. The semiconductor device according to claim 1,

the bonding material is disposed in an amount equal to or greater than 1/3 by volume of the volume of at least a part of the plurality of heat dissipation through holes that overlap the electronic component or the heat diffusion portion with the plurality of conductor layers interposed therebetween.

4. The semiconductor device according to any one of claims 1 to 3,

the heat diffusion section includes:

a 1 st portion extending in a direction along one main surface of the printed substrate and bonded to the one main surface of the printed substrate; and

and a 2 nd portion extending in a direction intersecting the 1 st portion.

5. The semiconductor device according to any one of claims 1 to 4,

the heat diffusion portion is bonded to both of at least a part of a 3 rd portion of the electronic component extending in a direction along the one main surface and at least a part of a 4 th portion of the electronic component extending in a direction intersecting the one main surface via the bonding material.

6. The semiconductor device according to any one of claims 1 to 5,

a part of the heat diffusion portion is disposed so as to cover a 2 nd surface of the electronic component on a side opposite to a 1 st surface facing one main surface of the printed substrate.

7. The semiconductor device according to any one of claims 1 to 6,

the printed substrate includes a plurality of the insulating layers,

each of the plurality of insulating layers includes inorganic filler particles.

8. The semiconductor device according to any one of claims 1 to 7,

the printed circuit board is provided with a groove for connecting the heat dissipation through holes adjacent to each other from a perspective of one main surface of the printed circuit board.

9. The semiconductor device according to any one of claims 1 to 8,

the heat diffusion sections are disposed in a plurality around the electronic component from a perspective of transmission through one main surface of the printed circuit board.

10. The semiconductor device according to any one of claims 1 to 8,

a plurality of electronic components are arranged at intervals from a transmission viewpoint of one main surface of the printed board,

the single heat diffusion portion is disposed around each of the plurality of electronic components.

11. The semiconductor device according to any one of claims 1 to 10,

the heat diffusion portion has a higher bending rigidity than the printed substrate.

12. The semiconductor device according to any one of claims 1 to 11,

at least a part of the electronic component and the heat diffusion portion is covered with a heat diffusion material.